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16. 30 people can fit in 6 rooms. How many people can fit in 1 room?

BODMAS Rules

We will obey the rules for simplifying an expression using BODMAS rules -
involving integers for solving order of operations.

Follow the order of operation as :
1. Bracket ® Solve inside the Brackets before Of, Multiply, Divide, Add or

Subtract.
For example :

7 × (15 + 5) = 7 × 20
= 140

2. Of ® Then, solve Of part (Powers, Roots, etc.,) before Multiply, Divide, Add
or Subtract. (“Of” means multiply, therefore 3 of 7 = 3 × 7

For example :
6 + 3 of 7 – 5
= 6 +3 × 7 – 5

= 6 + 21 – 5
= 27 – 5

= 22
3. Division/Multiplication ® Then, calculate Multiply or Divide before Add or
Subtract start from left to right.

For example :
20 + 21 by 3 × 2

= 20 + 7 × 2
= 20 + 14

= 34
4. Addition/Subtraction ® At last Add or Subtract start from left to right.

17 + (8 – 5) × 5
= 17 + 3 × 5

= 17 + 15
= 32

Example 28 : Simplify : 78 – [5 + 3 of (25 – 2 × 10)] (First we solve inside the Bracket ().)
Solution : = 78 – [5 + 3 of (25 – 20)], (Simplifying ‘multiplication' 2 × 10 = 20)
= 78 – [5 + 3 of 5], (Simplifying ‘subtraction' 25 – 20 = 5)

= 78 – [5 + 3 × 5], (Simplifying ‘of')
= 78 – [5 + 15], (Simplifying ‘multiplication' 3 × 5 = 15)

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Mathematics In Focus - 5