SSC CGL (Prelims) Maths: Mathematics questions with solutions

Q1. How many diagonals does a pentagon have?

1. 3
2. 5
3. 2
4. 4

Answer: 5

The number of diagonals in an n-sided polygon is given by n(n-3)/2. For a pentagon, n = 5, so the number of diagonals is 5(5-3)/2 = 5. Therefore, the answer is 5.

Q2. What is the value of \((4^2 + 3^2) / (7 - 2)\)?

1. 5
2. 4
3. 6
4. 7

Answer: 5

First, calculate the powers: 4^2 = 16 and 3^2 = 9, so the numerator is 25. The denominator is 7 - 2 = 5. Therefore, 25/5 = 5.

Q3. A train 150 m long is running at 54 km/h. In how much time will it pass a man standing on the platform?

1. 8 sec
2. 9 sec
3. 10 sec
4. 12 sec

Answer: 10 sec

The train must cover 150 m to pass the man. Converting 54 km/h to m/s gives 15 m/s, so time = 150/15 = 10 seconds.