Computation Operations

In this chapter, the concept of BODMAS is introduced.

Concept of BODMAS

BODMAS is a helpful tool in math that helps us remember the order in which we should solve math problems. It tells us the sequence in which we should solve different parts of a math problem when it has multiple operations.

The full form of BODMAS is:

→ B: Brackets
→ O: Orders (like square roots or exponents)
→ D: Division
→ M: Multiplication
→ A: Addition
→ S: Subtraction

Here is how the order of operations works:

First, we solve what is inside parentheses or brackets.

Then, we deal with exponents (like square roots and exponents).

Next, we do any multiplication or division from left to right. Multiplication and division are in the same family, so we can do them in any order among themselves.

Finally, we do any addition or subtraction from left to right. Addition and subtraction are also in the same family, so we can do them in any order among themselves.

Let us solve some examples based on BODMAS for class 4 to understand them better.

Example 1: Simplify the expression: 10 + 4 × (9 ÷ 3) − 5

a) 12
b) 17
c) 19
d) 22

Answer: b) 17

Explanation: Use BODMAS rule,

10 + 4 × (9 ÷ 3) − 5

= 10 + 4 × (3) − 5
= 10 + 12 − 5
= 22 − 5 
= 17

Example 2: Leo can walk 840 metres in 7 minutes. What distance can he walk in 3 minutes?

a) 300 metres
b) 320 metres
c) 300 metres
d) 360 metres

Answer: d) 360 metres

Explanation: Distance covered in 7 minutes = 840 metres
Distance covered in 1 minute = (840 ÷ 7) metres
Distance covered in 3 minutes = (840 ÷ 7) 3 [Using BODMAS rule]
= 120 × 3 
= 360 metres