Page 39 - Maths Skill - 6

Prime Time 37

Where V → Vinculum (also known as bar)
B → Bracket Fact-o-meter

O → Of � When no sign is given between a number and
D → Division a bracket, we perform the multiplication (×)
M → Multiplication there.
A → Addition i.e., 2 (5 + 4) = 2 × (5 + 4) = 2 × 9 = 18

S → Subtraction
The order of brackets followed is () {} []. Let us learn more through examples.
III III
Let’s Attempt

Example: Simplify the following:

(i) 72 – [1 + {49 ÷ (9 – 2)}] (ii) 63 2 155 2 1 54 1

Solution: (i) 72 – [1 + {49 ÷ (9 – 2)}] [Removing the parenthesis]
= 72 – [1 + {49 ÷ 7}] [Removing curly brackets]
= 72 – [1 + 7] [Removing square brackets]
= 72 – 8 = 64 [Subtracting 8 from 72]

(ii) 63 2 155 2 1 54 1

= 63 ÷ [2 + {15 ÷ 3}] ÷ [1 + (5 – 3)]
= 63 ÷ [2 + 5] ÷ [1 + 2]
= 63 ÷ 7 ÷ 3
= 9 ÷ 3 = 3

Exercise 3.1

1. Using brackets, write a mathematic expression for each of the following:

(i) Five is multiplied by the difference of 18 and 5.
(ii) Forty-five divided by the sum of 5 and 4.
(iii) Ninety divided by two more than the sum of 5 and 3.
(iv) Two multiplied by three less than the difference of 30 and 6.
2. Simplify the following expressions:

(i) 2[25 – 7(9 – 8) × {6 – (7 – 2)}] (ii) 88 150 39 5 253 8

(iii) 118 144 12 12 14 77 5 (iv) 425 240 90 50 45

3. Simplify:

(i) 10 – [8 – {8 ÷ 4 – (15 – 20 ÷ 4) ÷ 5}] (ii) 14 12 9 762

(iii) 16 – [11 – {8 ÷ (17 + 3 × 2 – 19)}] (iv) 145 – 3[25 + {90 ÷ (15 × 3 – 30)}]