Question

Simplify:
(i) (−24) × (68) + (−24) × 32
(ii) (−9) × 18 − (−9) × 8
(iii) (−147) ÷ (−21)
(iv) 16 ÷ (−1)

Answer 1

(i) (–24) × (68) + (–24) × 32
= –(24) × (68+32)
= –24 × 100
= –2400

(ii) (–9) × 18 – (–9) × 8
= –(9 ) × [18 – 8]
= –9 × 10
= –90

(iii) (–147) ÷ (–21)

$\begin{array}{l}=\frac{-147}{-21}\\ =\frac{(-1)\times 147}{(-1)\times 21}\\ =\frac{(-1)}{(-1)}\times \frac{147}{21}\\ =7\end{array}$

(iv) 16 ÷ (–1)

$\begin{array}{l}=\frac{16}{-1}\\ =\frac{16\times (-1)}{(-1)\times (-1)}\\ =16\times (-1)\\ =-16\end{array}$ {Multiplying the numerator and the denominator by (–1)}