1
Find the simple interest on ₹12,000 at 8% per annum for 3 years.
Correct answer: A. ₹2,880
SI = P × R × T ÷ 100 = 12000 × 8 × 3 ÷ 100 = ₹2,880.
easy
Interest, Time and Work, Speed and Distance MCQs
Simple and compound interest, time and work, pipes, trains, boats, averages and ratio MCQs with worked solutions for SSC and banking exams.
20 MCQsUpdated 27 October 2026
A mixed arithmetic set covering simple and compound interest, the difference between them, pipes filling and emptying a tank, average speed for a round trip, and averages of ages.
For average speed over equal distances, use 2xy ÷ (x + y), not the simple average of the two speeds. Each explanation shows the working.
- 2
A sum of ₹5,000 becomes ₹6,500 in 3 years at simple interest. What is the rate?
Correct answer: C. 10%
Interest = ₹1500. Rate = 1500 × 100 ÷ (5000 × 3) = 10% per annum.
medium - 3
In how many years will a sum double itself at 10% per annum simple interest?
Correct answer: A. 10 years
To double, the interest must equal the principal (100%). At 10% a year that takes 100 ÷ 10 = 10 years.
easy - 4
Find the compound interest on ₹10,000 at 10% per annum for 2 years, compounded annually.
Correct answer: C. ₹2,100
Amount = 10000 × 1.1 × 1.1 = ₹12,100. CI = 12,100 − 10,000 = ₹2,100.
medium - 5
What is the difference between compound and simple interest on ₹8,000 for 2 years at 5% per annum?
Correct answer: A. ₹20
For 2 years, CI − SI = P × (R/100)² = 8000 × 0.0025 = ₹20.
hard - 6
A can do a piece of work in 12 days and B in 24 days. In how many days can they finish it together?
Correct answer: A. 8 days
Together they do 1/12 + 1/24 = 3/24 = 1/8 of the work per day, so they need 8 days.
easy - 7
A and B together finish a job in 10 days. A alone takes 15 days. How long would B take alone?
Correct answer: B. 30 days
B's rate = 1/10 − 1/15 = 1/30 per day, so B alone needs 30 days.
medium - 8
12 workers can build a wall in 18 days. How many workers are needed to build it in 8 days?
Correct answer: C. 27
The job needs 12 × 18 = 216 worker-days. In 8 days you need 216 ÷ 8 = 27 workers.
medium - 9
A pipe fills a tank in 6 hours and a leak empties it in 9 hours. With both open, how long does the tank take to fill?
Correct answer: C. 18 hours
Net filling per hour = 1/6 − 1/9 = 1/18, so it takes 18 hours.
medium - 10
A speed of 54 km/h is equal to:
Correct answer: B. 15 m/s
Multiply by 5/18 to convert km/h to m/s: 54 × 5 ÷ 18 = 15 m/s.
easy - 11
A train 200 m long runs at 72 km/h. How long does it take to pass a signal pole?
Correct answer: B. 10 seconds
Speed = 72 × 5/18 = 20 m/s. To pass a pole it covers its own length: 200 ÷ 20 = 10 seconds.
easy - 12
A 150 m train at 72 km/h crosses a 250 m platform. How long does it take?
Correct answer: D. 20 seconds
Distance = train + platform = 400 m. Speed = 20 m/s. Time = 400 ÷ 20 = 20 seconds.
medium - 13
A car goes from A to B at 60 km/h and returns at 40 km/h. What is its average speed for the round trip?
Correct answer: D. 48 km/h
For equal distances, average speed = 2 × 60 × 40 ÷ (60 + 40) = 48 km/h, not the simple average of 50.
hard - 14
Two trains 240 km apart move towards each other at 45 km/h and 35 km/h. After how long will they meet?
Correct answer: C. 3 hours
When moving towards each other, speeds add: 45 + 35 = 80 km/h. Time = 240 ÷ 80 = 3 hours.
medium - 15
A bus covers 360 km in 4 hours. How far will it travel in 7 hours at the same speed?
Correct answer: D. 630 km
Speed = 360 ÷ 4 = 90 km/h, so in 7 hours it covers 90 × 7 = 630 km.
easy - 16
A boat's speed in still water is 15 km/h and the stream flows at 3 km/h. How long does it take to go 36 km upstream?
Correct answer: A. 3 hours
Upstream speed = 15 − 3 = 12 km/h. Time = 36 ÷ 12 = 3 hours.
medium - 17
The ages of four friends are 25, 30, 35, 40 years. What is their average age?
Correct answer: C. 32.5 years
Sum = 130, and 130 ÷ 4 = 32.5 years.
easy - 18
The average weight of 10 people is 50 kg. When one more person joins, the average becomes 52 kg. What is the newcomer's weight?
Correct answer: C. 72 kg
New total = 52 × 11 = 572; old total = 500. Newcomer = 72 kg.
medium - 19
₹2,400 is divided between Asha and Bina in the ratio 3 : 5. What is Bina's share?
Correct answer: B. ₹1,500
Total parts = 8; one part = 2400 ÷ 8 = ₹300. Bina gets 5 parts = ₹1,500.
easy - 20
What amount will ₹4,000 grow to in 2 years at 5% per annum compounded annually?
Correct answer: C. ₹4,410
A = 4000 × 1.05 × 1.05 = ₹4,410.
medium