Question

Evaluate using properties :

(i) 679 x 8 + 679 x 2

(ii) 284 x 12 – 284 x 2

(iii) 55873 x 94 + 55873 x 6

(iv) 7984 x 15 – 7984 x 5

(v) 8324 x 1945 – 8324 x 945

(vi) 3333 x 987 + 13 x 3333

Answer 1

(i) 679 x 8 + 679 x 2

= 679 x (8 + 2) (using distributivity)

= 679 x 10 = 6790

(ii) 284 x 12-284 x 2

= 284 x (12-2) (using distributivity)

= 284 x 10 = 2840

(iii) 55873 x 94 + 55873 x 6

= 55873 x (94 + 6) (using distributivity)

= 55873 x 100 = 5587300

(iv) 7984 x 15 – 7984 x 5

= 7984 x (15 – 5) (using distributivity)

= 7984 x 10 = 79840

(v) 8324 x 1.945 – 8324 x 945

= 8324 x (1945 – 945) (using distributivity)

= 8324 x 1000 = 8324000

(vi) 3333 x 987 + 13 x 3333

= 3333 x (987 + 13) (using distributivity)

= 3333 x 1000 = 3333000