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3841. A marked price of a railway staff uniform kit is ₹6832. A discount of 12% is offered during a department sale. What is the selling price? (SI Set 10)
- A. 5988.16
- B. 6012.16
- C. 5670.56
- D. 6055.16
Answer: 6012.16
Explanation: SP = MP x (1 - 12/100) = 6832 x 0.88 = 6012.16.
3842. A railway canteen vendor bought a stock of items for ₹4624 and sold it at a loss of 22%. Find the selling price. (SI Set 10)
- A. 3697.72
- B. 3606.72
- C. 3517.72
- D. 5641.28
Answer: 3606.72
Explanation: SP = CP x (1 - 22/100) = 4624 x 0.78 = 3606.72.
3843. The monthly ration budget of an RPF barrack was ₹1893. It was decreased by 10%. What is the new budget? (SI Set 10)
- A. 1693.7
- B. 1743.7
- C. 1703.7
- D. 2082.3
Answer: 1703.7
Explanation: New value = 1893 x (1 - 10/100) = 1703.7.
3844. In an RPF SI recruitment drive, 1369 candidates appeared for the written exam. If 18% of them qualified for the physical efficiency test, how many candidates qualified? (SI Set 10)
- A. 256.42
- B. 210.42
- C. 246.42
- D. 292.42
Answer: 246.42
Explanation: 18% of 1369 = (18/100) x 1369 = 246.42.
3845. Find the difference between the compound interest and simple interest on ₹25000 for 2 years at 15% per annum (an RPF finance-cell training problem). (SI Set 9)
- A. 1125
- B. 583.5
- C. 505.5
- D. 562.5
Answer: 562.5
Explanation: SI = (25000×15×2)/100 = 7500. CI = 25000[(1+15/100)²-1] = 8062.5. Difference = 8062.5 - 7500 = 562.5. (Shortcut: Diff = P(R/100)² for 2 years.)
3846. A sum of ₹30112 earns simple interest at 6% p.a. for 2 years under Scheme A, versus 11% p.a. for 4 years under Scheme B (an RPF welfare-fund comparison). Find the difference between the two interests. (SI Set 9)
- A. 16862.72
- B. 9635.84
- C. 9536.84
- D. 9704.84
Answer: 9635.84
Explanation: SI(A) = (30112×6×2)/100 = 3613.44. SI(B) = (30112×11×4)/100 = 13249.28. Difference = |3613.44 - 13249.28| = 9635.84.
3847. Three RPF maintenance workers can individually repair a section of boundary fencing in 11, 24, and 16 days respectively. Working together, how many days will they take to finish the job? (SI Set 9)
- A. 5.13
- B. 6.13
- C. 3.63
- D. 17
Answer: 5.13
Explanation: Combined rate = 1/11 + 1/24 + 1/16 per day. Time = 1/(1/11+1/24+1/16) = 5.13 days.
3848. Two RPF joggers start at the same point on a circular track of length 400 m and run in opposite directions at 5 m/s and 4 m/s. After how many seconds will they meet for the first time? (SI Set 9)
- A. 57.44
- B. 400
- C. 38.44
- D. 44.44
Answer: 44.44
Explanation: Relative speed (opposite directions) = 5+4 = 9 m/s. Time to meet = Circumference/Relative speed = 400/9 = 44.44 s.
3849. An RPF vehicle travels from post A to post B at 50 km/h and returns the same distance at 60 km/h. Find its average speed for the whole journey. (SI Set 9)
- A. 51.55
- B. 54.55
- C. 55
- D. 56.55
Answer: 54.55
Explanation: Average speed (equal distances) = 2×S1×S2/(S1+S2) = 2×50×60/(50+60) = 54.55 km/h.
3850. An RPF control room logs incident serial numbers from 1 to 48 in a single shift. Find the sum of all serial numbers. (SI Set 9)
- A. 1190
- B. 1176
- C. 1238
- D. 1161
Answer: 1176
Explanation: Sum = n(n+1)/2 = 48(48+1)/2 = 1176.
3851. An RPF SI officer's father's age is currently 5 times the officer's age of 14 years. Find the ratio of father's age to the officer's age after 9 years. (SI Set 9)
- A. 3.13
- B. 3.43
- C. 5
- D. 3.93
Answer: 3.43
Explanation: Father's current age = 5 × 14 = 70. After 9 years: Father = 79, Officer = 23. Ratio = 79/23 = 3.43.
3852. Two RPF canteen contract partners invest ₹8580 and ₹17492 respectively in a joint catering contract for the same period. If the total profit is ₹6925, find the first partner's share. (SI Set 9)
- A. 2925.94
- B. 4646.06
- C. 1978.94
- D. 2278.94
Answer: 2278.94
Explanation: Profit ratio = Capital ratio = 8580:17492. First partner's share = [8580/(8580+17492)] × 6925 = 2278.94.
3853. An RPF canteen mixes two grades of rice costing ₹49/kg and ₹86/kg to get a mixture worth ₹83/kg. Find the ratio in which they must be mixed. (SI Set 9)
- A. 3:34
- B. 4:34
- C. 34:3
- D. 3:35
Answer: 3:34
Explanation: By alligation: ratio = (CP2-Mean):(Mean-CP1) = (86-83):(83-49) = 3:34 = 3:34 (simplified).
3854. Two fair dice are rolled together by an RPF training instructor during a probability drill. What is the probability that the sum of the numbers is 7? (SI Set 9)
- A. 0.01
- B. 0.17
- C. 0.43
- D. 0.28
Answer: 0.17
Explanation: Number of favorable outcomes (sum=7) = 6. Total outcomes = 36. Probability = 6/36 = 0.17.
3855. From a group of 7 RPF SI candidates, in how many ways can a team (unordered) of 2 be selected? (SI Set 9)
- A. 42
- B. 43
- C. 21
- D. 7
Answer: 21
Explanation: nCr = n!/(r!(n-r)!) = 7!/(2!×5!) = 21.
3856. The bar graph shows the number of RPF SI cases resolved per year: 2021=1052, 2022=2197, 2023=1295, 2024=1193, 2025=566. Find the difference in cases resolved between 2024 and 2025. (SI Set 9)
- A. 648
- B. 627
- C. 640
- D. 619
Answer: 627
Explanation: Difference = |1193 - 566| = 627.
3857. A pie chart shows the RPF annual budget of ₹5400000 divided among 5 heads by central angle: Equipment=73°, Training=87°, Welfare=79°, Infrastructure=104°, Communication=17°. Find the budget allocated to Equipment. (SI Set 9)
- A. ₹1078722
- B. ₹1305000
- C. ₹1141322
- D. ₹1095000
Answer: ₹1095000
Explanation: Share = (73°/360°) × 5400000 = 1095000.
3858. The table shows RPF SI recruits across 5 zones: North=256, South=167, East=282, West=279, Central=383. Find the average number of recruits per zone. (SI Set 9)
- A. 267.4
- B. 273.4
- C. 294.4
- D. 281.4
Answer: 273.4
Explanation: Total = 1367. Average = 1367/5 = 273.4.
3859. An RPF watchtower is 29 m tall. From a point on the ground, the angle of elevation to the top of the tower is 60°. Find the horizontal distance from the point to the base of the tower. (tan 60° = 1.732) (SI Set 9)
- A. 50.23
- B. 11.74
- C. 16.74
- D. 22.74
Answer: 16.74
Explanation: tan(60°) = height/distance => distance = height/tan(60°) = 29/1.732 = 16.74 m.
3860. An RPF storage container is a cuboid of dimensions 11 m × 6 m × 5 m. Find its total surface area. (SI Set 9)
- A. 255
- B. 414
- C. 302
- D. 341
Answer: 302
Explanation: TSA = 2(lw+wh+hl) = 2(66+30+55) = 302 sq m.
3861. A circular RPF watchtower base has a radius of 49 m. Find its circumference. (Use π = 22/7) (SI Set 9)
- A. 7546
- B. 294
- C. 324
- D. 308
Answer: 308
Explanation: Circumference = 2πr = 2 × (22/7) × 49 = 308 m.
3862. A rectangular RPF parade ground is 38 m long and 34 m wide. Find its perimeter. (SI Set 9)
- A. 155
- B. 1292
- C. 144
- D. 124
Answer: 144
Explanation: Perimeter = 2(length + width) = 2(38+34) = 144 m.
3863. If x² - 18x + 77 = 0 are the roots representing two patrol-team sizes, find the larger root. (SI Set 9)
- A. 7
- B. 11
- C. 6
- D. 15
Answer: 11
Explanation: Factorizing: x² - 18x + 77 = (x - 7)(x - 11) = 0. Roots are 7 and 11. Larger root = 11.
3864. In an RPF duty-roster puzzle, if 4x + 24 = 48, find the value of x. (SI Set 9)
- A. 7
- B. 3
- C. 12
- D. 6
Answer: 6
Explanation: 4x = 48 - 24 = 24. x = 24/4 = 6.
3865. Simplify: 7 × (4/10) + 4 = ? (SI Set 9)
- A. 11.4
- B. 6.8
- C. 9.8
- D. 6.3
Answer: 6.8
Explanation: 7 × (4/10) = 2.8. Adding 4: 2.8 + 4 = 6.8.
3866. Simplify: 16 + 11 × 13 − 5 + 20 = ? (SI Set 9)
- A. 174
- B. 366
- C. 169
- D. 184
Answer: 174
Explanation: By BODMAS: 11 × 13 = 143 first. Then 16 + 143 - 5 + 20 = 174.
3867. In an RPF stores ledger, 37748 cartridge boxes need to be arranged into equal rows for a divisor of 9. What is the least number of boxes that must be added to make the total exactly divisible by 9? (SI Set 9)
- A. 2
- B. 9
- C. 6
- D. 7
Answer: 7
Explanation: 37748 mod 9 = 2. Number to add = 9 - 2 = 7 (0 if already divisible).
3868. Find the LCM of the patrol shift durations 14 minutes and 55 minutes used for syncing two RPF post schedules. (SI Set 9)
- A. 1
- B. 766
- C. 772
- D. 770
Answer: 770
Explanation: LCM(14, 55) = (14 x 55)/HCF(14,55) = (14 x 55)/1 = 770.
3869. An inlet pipe at a railway water tank can fill it in 20 hours, while an outlet pipe (leak) can empty it in 22 hours. If both are opened together, in how many hours will the tank be filled? (SI Set 9)
- A. 220
- B. 218.5
- C. 21
- D. 225
Answer: 220
Explanation: Net rate = 1/20 - 1/22 per hour. Time to fill = 1/(1/20 - 1/22) = 220 hours.
3870. RPF constable A can clear a stretch of railway track of debris alone in 25 days, and constable B can do it alone in 8 days. Working together, in how many days will they finish the job? (SI Set 9)
- A. 9.06
- B. 5.06
- C. 6.06
- D. 16.5
Answer: 6.06
Explanation: Combined time = (A x B)/(A+B) = (25 x 8)/(25+8) = 6.06 days.
3871. A boat used for river patrol by RPF has a speed of 11 km/h in still water. The current speed is 2 km/h. Find the time taken to cover 113 km downstream. (SI Set 9)
- A. 8.19
- B. 10.69
- C. 10.27
- D. 8.69
Answer: 8.69
Explanation: Downstream speed = 11 + 2 = 13 km/h. Time = 113/13 = 8.69 hours.
3872. Two trains of lengths 164 m and 189 m run on parallel tracks in opposite directions at 36 km/h and 36 km/h respectively. Find the time they take to cross each other completely. (SI Set 9)
- A. 353
- B. 19.65
- C. 12.65
- D. 17.65
Answer: 17.65
Explanation: Relative speed (opposite dir) = (36+36) x 5/18 = 20 m/s. Total length = 164+189 = 353 m. Time = 353/20 = 17.65 s.
3873. A railway goods train 158 m long is moving at a speed of 63 km/h. How much time will it take to cross a stationary signal pole? (SI Set 9)
- A. 3.03
- B. 9.03
- C. 16.03
- D. 8.1
Answer: 9.03
Explanation: Speed = 63 x 5/18 = 17.5 m/s. Time = Length/Speed = 158/17.5 = 9.03 seconds.
3874. An RPF patrol vehicle covers a distance of 841 km at a constant speed of 30 km/h. How much time does it take? (SI Set 9)
- A. 29.53
- B. 28.03
- C. 21.03
- D. 26.53
Answer: 28.03
Explanation: Time = Distance/Speed = 841/30 = 28.03 hours.
3875. The average daily patrol distance of 9 RPF beat officers is 62 km. One officer who covered only 55 km is excluded. Find the new average distance of the remaining officers. (SI Set 9)
- A. 62.88
- B. 63.88
- C. 62
- D. 60.88
Answer: 62.88
Explanation: Total = 9 x 62 = 558. New total = 558 - 55 = 503. New average = 503/8 = 62.88.
3876. The average age of 9 RPF SI trainees is 64 years. A new trainee aged 57 years joins the batch. Find the new average age. (SI Set 9)
- A. 64
- B. 64.3
- C. 58.3
- D. 63.3
Answer: 63.3
Explanation: Old total = 9 x 64 = 576. New total = 576 + 57 = 633. New average = 633/10 = 63.3.
3877. If 9 railway signal poles cost the same as 13 units cost 14 units of a fourth quantity (9:13 :: 14:x), find x. (SI Set 9)
- A. 10.22
- B. 20.22
- C. 9.69
- D. 24.22
Answer: 20.22
Explanation: 9:13 :: 14:x => x = (13 x 14)/9 = 20.22.
3878. A sum of ₹350 is divided between two RPF constables in the ratio 2:3 as duty allowance. Find the share of the first constable. (SI Set 9)
- A. 140
- B. 129
- C. 210
- D. 170
Answer: 140
Explanation: First share = [2/(2+3)] x 350 = 140.
3879. Find the compound interest on ₹40000 for 3 years at 20% per annum compounded annually, for a railway pension-fund deposit. (SI Set 9)
- A. 28923
- B. 29120
- C. 24000
- D. 29292
Answer: 29120
Explanation: A = P(1+R/100)^T = 40000(1+20/100)^3 = 69120. CI = A - P = 69120 - 40000 = 29120.
3880. A railway cooperative society lends ₹10017 to a staff member at 4% per annum simple interest for 4 years. Find the simple interest. (SI Set 9)
- A. 1602.72
- B. 1352.72
- C. 1748.72
- D. 2003.4
Answer: 1602.72
Explanation: SI = (P x R x T)/100 = (10017 x 4 x 4)/100 = 1602.72.
3881. A railway equipment supplier offers successive discounts of 25% and 5% on a marked price of ₹3882. Find the final selling price. (SI Set 9)
- A. 2739.93
- B. 2717.4
- C. 2765.93
- D. 2817.93
Answer: 2765.93
Explanation: SP = 3882 x (1-25/100) x (1-5/100) = 3882 x 0.75 x 0.95 = 2765.93.
3882. A marked price of a railway staff uniform kit is ₹712. A discount of 18% is offered during a department sale. What is the selling price? (SI Set 9)
- A. 583.84
- B. 662.84
- C. 528.84
- D. 548.24
Answer: 583.84
Explanation: SP = MP x (1 - 18/100) = 712 x 0.8200000000000001 = 583.84.
3883. A railway canteen vendor bought a stock of items for ₹6457 and sold it at a profit of 18%. Find the selling price. (SI Set 9)
- A. 7589.26
- B. 5294.74
- C. 7619.26
- D. 7642.26
Answer: 7619.26
Explanation: SP = CP x (1 + 18/100) = 6457 x 1.18 = 7619.26.
3884. The monthly ration budget of an RPF barrack was ₹1921. It was decreased by 30%. What is the new budget? (SI Set 9)
- A. 1344.7
- B. 1399.7
- C. 1327.7
- D. 2497.3
Answer: 1344.7
Explanation: New value = 1921 x (1 - 30/100) = 1344.7.
3885. In an RPF SI recruitment drive, 1497 candidates appeared for the written exam. If 35% of them qualified for the physical efficiency test, how many candidates qualified? (SI Set 9)
- A. 574.95
- B. 523.95
- C. 541.95
- D. 513.95
Answer: 523.95
Explanation: 35% of 1497 = (35/100) x 1497 = 523.95.
3886. Find the difference between the compound interest and simple interest on ₹25000 for 2 years at 15% per annum (an RPF finance-cell training problem). (SI Set 8)
- A. 562.5
- B. 626.5
- C. 1125
- D. 503.5
Answer: 562.5
Explanation: SI = (25000×15×2)/100 = 7500. CI = 25000[(1+15/100)²-1] = 8062.5. Difference = 8062.5 - 7500 = 562.5. (Shortcut: Diff = P(R/100)² for 2 years.)
3887. A sum of ₹8991 earns simple interest at 10% p.a. for 5 years under Scheme A, versus 7% p.a. for 2 years under Scheme B (an RPF welfare-fund comparison). Find the difference between the two interests. (SI Set 8)
- A. 3116.76
- B. 3373.76
- C. 3236.76
- D. 5754.24
Answer: 3236.76
Explanation: SI(A) = (8991×10×5)/100 = 4495.5. SI(B) = (8991×7×2)/100 = 1258.74. Difference = |4495.5 - 1258.74| = 3236.76.
3888. Three RPF maintenance workers can individually repair a section of boundary fencing in 24, 24, and 15 days respectively. Working together, how many days will they take to finish the job? (SI Set 8)
- A. 21
- B. 6.67
- C. 5.67
- D. 10.67
Answer: 6.67
Explanation: Combined rate = 1/24 + 1/24 + 1/15 per day. Time = 1/(1/24+1/24+1/15) = 6.67 days.
3889. Two RPF joggers start at the same point on a circular track of length 300 m and run in opposite directions at 10 m/s and 5 m/s. After how many seconds will they meet for the first time? (SI Set 8)
- A. 34
- B. 8
- C. 20
- D. 60
Answer: 20
Explanation: Relative speed (opposite directions) = 10+5 = 15 m/s. Time to meet = Circumference/Relative speed = 300/15 = 20 s.
3890. An RPF vehicle travels from post A to post B at 60 km/h and returns the same distance at 60 km/h. Find its average speed for the whole journey. (SI Set 8)
- A. 57
- B. 60
- C. 84
- D. 66
Answer: 60
Explanation: Average speed (equal distances) = 2×S1×S2/(S1+S2) = 2×60×60/(60+60) = 60 km/h.
3891. An RPF control room logs incident serial numbers from 1 to 19 in a single shift. Find the sum of all serial numbers. (SI Set 8)
- A. 252
- B. 214
- C. 190
- D. 173
Answer: 190
Explanation: Sum = n(n+1)/2 = 19(19+1)/2 = 190.
3892. An RPF SI officer's father's age is currently 3 times the officer's age of 19 years. Find the ratio of father's age to the officer's age after 14 years. (SI Set 8)
- A. 3
- B. 1.85
- C. 2.15
- D. 2.65
Answer: 2.15
Explanation: Father's current age = 3 × 19 = 57. After 14 years: Father = 71, Officer = 33. Ratio = 71/33 = 2.15.
3893. Two RPF canteen contract partners invest ₹38704 and ₹22332 respectively in a joint catering contract for the same period. If the total profit is ₹21150, find the first partner's share. (SI Set 8)
- A. 13597.59
- B. 7738.41
- C. 13211.59
- D. 13411.59
Answer: 13411.59
Explanation: Profit ratio = Capital ratio = 38704:22332. First partner's share = [38704/(38704+22332)] × 21150 = 13411.59.
3894. An RPF canteen mixes two grades of rice costing ₹52/kg and ₹90/kg to get a mixture worth ₹58/kg. Find the ratio in which they must be mixed. (SI Set 8)
- A. 16:3
- B. 17:3
- C. 16:4
- D. 3:16
Answer: 16:3
Explanation: By alligation: ratio = (CP2-Mean):(Mean-CP1) = (90-58):(58-52) = 32:6 = 16:3 (simplified).
3895. An RPF stores bag contains 8 red, 8 blue, and 5 green signal flags. One flag is drawn at random. Find the probability that it is blue. (SI Set 8)
- A. 0.49
- B. 0.21
- C. 0.38
- D. 0.58
Answer: 0.38
Explanation: Total flags = 8+8+5 = 21. Probability(blue) = 8/21 = 0.38.
3896. From a group of 6 RPF SI candidates, in how many ways can a team (unordered) of 2 be selected? (SI Set 8)
- A. 10
- B. 20
- C. 30
- D. 15
Answer: 15
Explanation: nCr = n!/(r!(n-r)!) = 6!/(2!×4!) = 15.
3897. The bar graph shows the number of RPF SI cases resolved per year: 2021=1688, 2022=783, 2023=1958, 2024=2474, 2025=1943. Find the difference in cases resolved between 2021 and 2024. (SI Set 8)
- A. 804
- B. 779
- C. 822
- D. 786
Answer: 786
Explanation: Difference = |1688 - 2474| = 786.
3898. A pie chart shows the RPF annual budget of ₹9000000 divided among 5 heads by central angle: Equipment=111°, Training=89°, Welfare=114°, Infrastructure=31°, Communication=15°. Find the budget allocated to Equipment. (SI Set 8)
- A. ₹2775000
- B. ₹2747935
- C. ₹2795005
- D. ₹2225000
Answer: ₹2775000
Explanation: Share = (111°/360°) × 9000000 = 2775000.
3899. The table shows RPF SI recruits across 5 zones: North=149, South=207, East=180, West=312, Central=393. Find the ratio of recruits in West zone to South zone in simplest form. (SI Set 8)
- A. 90:69
- B. 46:69
- C. 104:69
- D. 125:69
Answer: 104:69
Explanation: Ratio = 312:207 = 104:69 (dividing by HCF 3).
3900. An RPF watchtower is 38 m tall. From a point on the ground, the angle of elevation to the top of the tower is 30°. Find the horizontal distance from the point to the base of the tower. (tan 30° = 0.577) (SI Set 8)
- A. 65.86
- B. 58.86
- C. 21.93
- D. 70.86
Answer: 65.86
Explanation: tan(30°) = height/distance => distance = height/tan(30°) = 38/0.577 = 65.86 m.
3901. An RPF storage container is a cuboid of dimensions 19 m × 10 m × 3 m. Find its volume. (SI Set 8)
- A. 661
- B. 646
- C. 539
- D. 570
Answer: 570
Explanation: Volume = l × w × h = 19 × 10 × 3 = 570 cu m.
3902. A circular RPF watchtower base has a radius of 42 m. Find its area. (Use π = 22/7) (SI Set 8)
- A. 5495
- B. 5544
- C. 5587
- D. 264
Answer: 5544
Explanation: Area = πr² = (22/7) × 42 × 42 = 5544 sq m.
3903. A rectangular RPF parade ground is 28 m long and 19 m wide. Find its area. (SI Set 8)
- A. 532
- B. 525
- C. 564
- D. 94
Answer: 532
Explanation: Area = length × width = 28 × 19 = 532 sq m.
3904. If x² - 6x + 8 = 0 are the roots representing two patrol-team sizes, find the larger root. (SI Set 8)
- A. 4
- B. 1
- C. 2
- D. 8
Answer: 4
Explanation: Factorizing: x² - 6x + 8 = (x - 4)(x - 2) = 0. Roots are 4 and 2. Larger root = 4.
3905. In an RPF duty-roster puzzle, if 3x + 7 = 76, find the value of x. (SI Set 8)
- A. 25.33
- B. 23
- C. 22
- D. 25
Answer: 23
Explanation: 3x = 76 - 7 = 69. x = 69/3 = 23.
3906. Simplify: 8 × (3/5) + 7 = ? (SI Set 8)
- A. 15.6
- B. 10.8
- C. 12.8
- D. 11.8
Answer: 11.8
Explanation: 8 × (3/5) = 4.8. Adding 7: 4.8 + 7 = 11.8.
3907. Simplify: 30 + 12 × 9 − 8 + 16 = ? (SI Set 8)
- A. 143
- B. 146
- C. 386
- D. 156
Answer: 146
Explanation: By BODMAS: 12 × 9 = 108 first. Then 30 + 108 - 8 + 16 = 146.
3908. In an RPF stores ledger, 52494 cartridge boxes need to be arranged into equal rows for a divisor of 19. What is the least number of boxes that must be added to make the total exactly divisible by 19? (SI Set 8)
- A. 7
- B. 1
- C. 3
- D. 16
Answer: 3
Explanation: 52494 mod 19 = 16. Number to add = 19 - 16 = 3 (0 if already divisible).
3909. Find the LCM of the patrol shift durations 49 minutes and 60 minutes used for syncing two RPF post schedules. (SI Set 8)
- A. 1
- B. 2934
- C. 2940
- D. 2947
Answer: 2940
Explanation: LCM(49, 60) = (49 x 60)/HCF(49,60) = (49 x 60)/1 = 2940.
3910. An inlet pipe at a railway water tank can fill it in 23 hours, while an outlet pipe (leak) can empty it in 14 hours. If both are opened together, in how many hours will the tank be filled? (SI Set 8)
- A. 35.28
- B. 35.78
- C. 18.5
- D. 39.78
Answer: 35.78
Explanation: Net rate = 1/23 - 1/14 per hour. Time to fill = 1/(1/23 - 1/14) = 35.78 hours.
3911. RPF constable A can clear a stretch of railway track of debris alone in 12 days, and constable B can do it alone in 24 days. Working together, in how many days will they finish the job? (SI Set 8)
- A. 12
- B. 7.5
- C. 18
- D. 8
Answer: 8
Explanation: Combined time = (A x B)/(A+B) = (12 x 24)/(12+24) = 8 days.
3912. A boat used for river patrol by RPF has a speed of 18 km/h in still water. The current speed is 4 km/h. Find the time taken to cover 66 km upstream. (SI Set 8)
- A. 3.67
- B. 3.71
- C. 6.71
- D. 4.71
Answer: 4.71
Explanation: Upstream speed = 18 - 4 = 14 km/h. Time = 66/14 = 4.71 hours.
3913. Two trains of lengths 154 m and 186 m run on parallel tracks in opposite directions at 36 km/h and 27 km/h respectively. Find the time they take to cross each other completely. (SI Set 8)
- A. 14.43
- B. 19.43
- C. 136
- D. 24.43
Answer: 19.43
Explanation: Relative speed (opposite dir) = (36+27) x 5/18 = 17.5 m/s. Total length = 154+186 = 340 m. Time = 340/17.5 = 19.43 s.
3914. A railway goods train 149 m long is moving at a speed of 81 km/h. How much time will it take to cross a stationary signal pole? (SI Set 8)
- A. 6.62
- B. 14.62
- C. 6.08
- D. 1.62
Answer: 6.62
Explanation: Speed = 81 x 5/18 = 22.5 m/s. Time = Length/Speed = 149/22.5 = 6.62 seconds.
3915. An RPF patrol vehicle covers a distance of 763 km at a constant speed of 40 km/h. How much time does it take? (SI Set 8)
- A. 19.08
- B. 15.26
- C. 17.58
- D. 20.58
Answer: 19.08
Explanation: Time = Distance/Speed = 763/40 = 19.08 hours.
3916. The average daily patrol distance of 11 RPF beat officers is 54 km. One officer who covered only 39 km is excluded. Find the new average distance of the remaining officers. (SI Set 8)
- A. 60.5
- B. 54
- C. 53.5
- D. 55.5
Answer: 55.5
Explanation: Total = 11 x 54 = 594. New total = 594 - 39 = 555. New average = 555/10 = 55.5.
3917. The average age of 8 RPF SI trainees is 79 years. A new trainee aged 74 years joins the batch. Find the new average age. (SI Set 8)
- A. 74.44
- B. 78.44
- C. 79
- D. 79.44
Answer: 78.44
Explanation: Old total = 8 x 79 = 632. New total = 632 + 74 = 706. New average = 706/9 = 78.44.
3918. If 15 railway signal poles cost the same as 14 units cost 15 units of a fourth quantity (15:14 :: 15:x), find x. (SI Set 8)
- A. 14
- B. 16
- C. 16.07
- D. 10
Answer: 14
Explanation: 15:14 :: 15:x => x = (14 x 15)/15 = 14.
3919. A sum of ₹156 is divided between two RPF constables in the ratio 4:2 as duty allowance. Find the share of the first constable. (SI Set 8)
- A. 104
- B. 52
- C. 135
- D. 70
Answer: 104
Explanation: First share = [4/(4+2)] x 156 = 104.
3920. Find the compound interest on ₹25000 for 3 years at 20% per annum compounded annually, for a railway pension-fund deposit. (SI Set 8)
- A. 15000
- B. 18311
- C. 18200
- D. 18127
Answer: 18200
Explanation: A = P(1+R/100)^T = 25000(1+20/100)^3 = 43200. CI = A - P = 43200 - 25000 = 18200.
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