Page 43 - Start Up Mathematics_5
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BODMAS Rule—Order of Operations
The four basic operations are addition, subtraction, multiplication and division.
The order of these operations is given by a rule called BODMAS. According to the rule, we
solve a problem in the given order.
B → Brackets (first)
O → Of (second)
D → Division (third)
M → Multiplication (fourth)
A → Addition (fifth)
S → Subtraction (sixth)
We will learn about the operation ‘Of’ in higher classes.
Example 29: Simplify 5 + 7 × 4. A Challenge!
Solution: 5 + 7 × 4 (multiply)
(128 ÷ 2) ÷ 2 ÷ 2 ÷ 2 ÷ 2 = ?
= 5 + 28 (add)
= 33
Example 30: Simplify 12 ÷ 2 + (15 – 4).
Solution: 12 ÷ 2 + (15 – 4) (brackets)
= 12 ÷ 2 + 11 (divide)
= 6 + 11 (add)
= 17
Example 31: Simplify 26 + 11 × 3 – 19.
Solution: 26 + 11 × 3 – 19 (multiply)
= 26 + 33 – 19 (add)
= 59 – 19 (subtract)
= 40
Example 32: Simplify 12 ÷ 6 × 3 ÷ 2.
Quick Tip
Solution: 12 ÷ 6 × 3 ÷ 2 (divide)
Since this problem has only
= 2 × 3 ÷ 2 (multiply) division and multiplication,
= 6 ÷ 2 (divide) move from left to right.
= 3
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