Numerical Ability Reviewer Part 17 with Answers

Part 17 of our Numerical Ability reviewer has 20 practice questions in the style of the Civil Service Exam. Answer them in order, read the explanation after each one, and check your score against the 80% passing mark at the end. Questions and choices are reshuffled every time you retake the part.

Start Part 17

Sample questions from Part 17

Here are a few questions from this part. Take the full test to answer all 20 and get your score.

Sample question 1

Which one of the following numbers is divisible by 3?

2345678
2876423
4006020
9566003

Answer: 4006020

A number is divisible by 3 if the sum of its digits is divisible by 3. The sum of digits of 4006020 is 4+0+0+6+0+2+0 = 12, which is divisible by 3.

Sample question 2

How many of the integers between 110 and 120 are prime numbers?

Answer: 1

The primes between 110 and 120 are 113 and 127 (but 127 is not included). Only 113 is prime, so there is 1 prime.

Sample question 3

The sum of all the prime numbers from 1 to 20 is

Answer: 77

Primes from 1 to 20: 2, 3, 5, 7, 11, 13, 17, 19. Their sum is 77.

Sample question 4

A city has a population of 300,000 out of which 180,000 are males. 50% of the population is literate. If 70% of the males are literate, then the percentage of females who are literate i

Answer: 20%

Total literates = 50% of 300,000 = 150,000. Literate males = 70% of 180,000 = 126,000. Therefore female literates = 150,000 − 126,000 = 24,000. Number of females = 120,000. Female literacy percentage = 24,000 / 120,000 × 100 = 20%.

Sample question 5

In an examination, 80% of the students passed in English, 85% in Mathematics and 75% in both English and Mathematics. If 40 students failed in both the subjects the total number of students is _____

Answer: 400

Using set formula: Failed both = 100% − (80% + 85% − 75%) = 100% − 90% = 10%. If 10% = 40 students, total = 40 ÷ 0.10 = 400.

Numerical Ability Reviewer - Part 17