Practice tests · Bank exams

Average practice questions for bank exams

By the PrepMatic team · Updated 9 Oct 2026 · 4 min read

The average of a group is the sum of its values divided by how many there are. Bank-exam questions rarely ask for a plain average. They change the group by adding or removing a member, overlap two groups, or mix groups of different sizes. One habit solves nearly all of them: work with sums, not averages. The five questions below are at prelims level.

Working with sums

Five practice questions

Question 1

The average of five numbers is 42. If one of the numbers, 30, is removed, what is the average of the remaining four numbers?

• A. 42
• B. 44
• C. 45
• D. 48

Question 2

The average age of 30 students in a class is 14 years. When the teacher's age is included, the average rises by 1 year. What is the teacher's age?

• A. 41 years
• B. 45 years
• C. 46 years
• D. 51 years

Question 3

The average of 11 numbers is 60. The average of the first six is 58 and the average of the last six is 63. What is the sixth number?

• A. 66
• B. 64
• C. 62
• D. 60

Question 4

A batsman's average after 11 innings is a certain value. In his 12th innings he scores 80 runs, which raises his average by 3. What is his average after the 12th innings?

• A. 44
• B. 45
• C. 46
• D. 47

Question 5

The average marks of 40 students in section A is 72, and of 60 students in section B is 82. What is the average marks of all 100 students?

• A. 76
• B. 77
• C. 78
• D. 80

Answers and explanations

1. C. The sum of five numbers is 5 × 42 = 210. Removing 30 leaves 180 for four numbers, so the average is 180 ÷ 4 = 45.
2. B. The class plus teacher has 31 people at an average of 15, a sum of 465. The students alone sum to 30 × 14 = 420. The teacher is 465 − 420 = 45 years old. The shortcut is 15 + 30 × 1 = 45.
3. A. The first six sum to 6 × 58 = 348 and the last six to 6 × 63 = 378. Together that is 726, but the sixth number is counted twice. All 11 sum to 11 × 60 = 660, so the sixth number is 726 − 660 = 66.
4. D. Let the average after 11 innings be a. Then 11a + 80 = 12(a + 3), so a = 44, and the new average is 47. The shortcut: 80 = new average + 3 × 11, so new average = 80 − 33 = 47.
5. C. The total marks are 40 × 72 + 60 × 82 = 2,880 + 4,920 = 7,800. Divide by 100 to get 78. The simple middle value 77 is the trap, because section B is the larger group.

How to prepare averages

• Convert every average into a sum. Multiply average by count first. Most averages questions then reduce to plain addition and subtraction.
• Use the "extra" shortcut. When a new value raises the average by d for n old values, that value exceeds the new average by d × n (Questions 2 and 4). It avoids forming an equation.
• Try the assumed-average method for weighted problems. In Question 5, take 72 as the base: section B is 10 above it, so 60 × 10 ÷ 100 = 6, and the average is 72 + 6 = 78.
• Watch for double counting. Overlapping groups, as in Question 3, count one member twice. Write down which one.
• Check where the answer must lie. A weighted average always falls between the two group averages, and nearer to the average of the group with more members.
• Link to other topics. Average speed uses a different formula, covered in time, speed and distance, and average age problems continue in ages.

Aim for 30 to 40 seconds each. Practise a mix of removal, replacement and weighted questions, because all three types come up.

The full averages topic test is on PrepMatic (about 15 questions, 30 minutes). The Quantitative Aptitude guide shows where averages sit among the other Quant topics, and the bank exam hub has each exam's pattern.

← All practice tests