Q. 154.0( 2 Votes )

# Write five situations for the following where brackets would be necessary.

(a) 7(8 – 3)

(b) (7 + 2) (10 – 3)

Answer :

(a) 7(8 – 3)

Here 7(8 – 3)

Multiply 7 by each number by opening brackets

= (7×8) – (7×3)

= 56 – 21

= 35

Also By BODMAS, solve the bracket first -

= 7(8 – 3)

= 7×5

= 35

(b) (7 + 2)(10 – 3)

Here,(7 + 2)(10 – 3)

By opening brackets

= 7(10 – 3) + 2(10 – 3)

= {(7×10) – (7×3)} + {(2×10 – 2×3)}

= {70 – 21} + {20 – 6}

= 49 + 14

= 63

Also by BODMAS, solve the brackets -

= (7 + 2) (10 – 3)

= 9 × 7

= 63

Also solving 1^{st} bracket then opening 2^{nd} bracket

= (7 + 2)(10 – 3)

= 9(10 – 3)

= (9 x 10) – (9 x 3)

= 90 – 27

= 63

Again, solving 2^{nd} bracket then opening 1^{st} bracket

= (7 + 2)(10 – 3)

= (7 + 2)7

= (7 x 7) + (2 x 7)

= 49 + 14

= 63

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