Question

Simplify. [Use the formula a × b + a × c = a (b + c)]

(1) 9 × 38 + 9 × 12
(2) 125 × 69 + 125 × 31
(3) 594 × 210 + 594 × 290
(4) 16 × 81 + 34 × 81

Answer 1

(1) a × b + a × c = a (b + c)
∴ 9 × 38 + 9 × 12
= 9 (38 + 12)
= 9 (50)
= 9 × 50
= 450

(2) a × b + a × c = a (b + c)
∴ 125 × 69 + 125 × 31
= 125 (69 + 31)
= 125 (100)
= 125 × 100
= 12500

(3) a × b + a × c = a (b + c)
∴ 594 × 210 + 594 × 290
= 594 (210 + 290)
= 594 (500)
= 594 × 500
= 297000

(4) a × b + a × c = a (b + c)
∴ 16 × 81 + 34 × 81
= 81 (16 + 34)
= 81 (50)
= 81 × 50
= 4050