Question

Use convenient groupings and find the values of
(i) 18 × (−27) × 30
(ii) (−8) × (−63) × 9
(iii) (−17) × (−23) × 41
(iv) (−51) × (−47) × (−19)

Answer 1

(i) 18 × (–27) × 30
= (–27) × [18 × 30]
= (–27) × 540
= –14580

(ii) (–8) × (–63) × 9
= [(–8) × (–63)] × 9
= 504 × 9
= 4536

(iii) (–17) × (–23) × 41
= [(–17) × (–23)] × 41
= 391 × 41
= 16031

(iv) (–51) × (–47) × (–19)
= [(–51) × (–47)] × (–19)
= 2397 × (–19)
= – 45543