RRB NTPC Mathematics 1

Question 1

A train travels 360 km in 4 hours. What is its speed in km/h?

Accepted Answer

90

Answer

Speed = Distance ÷ Time = 360 ÷ 4 = 90 km/h.

Question 2

The LCM of 12 and 18 is:

Accepted Answer

36

Answer

The LCM of 12 and 18 is 36 because 36 is the smallest number divisible by both.

Question 3

If a number is increased by 20% and then decreased by 20%, the net change is:

Accepted Answer

4% decrease

Answer

After a 20% increase and 20% decrease, the net effect is a 4% decrease (100 × 1.2 × 0.8 = 96).

Question 4

What is the simple interest on ₹5,000 at 8% per annum for 3 years?

Accepted Answer

₹1,200

Answer

SI = (P × R × T) / 100 = (5000 × 8 × 3) / 100 = ₹1,200.

Question 5

The ratio of two numbers is 3:5 and their sum is 64. The larger number is:

Accepted Answer

40

Answer

The larger number = (5/8) × 64 = 40, since 5 parts out of a total of 8 parts.

RRB NTPC Practice Test