Question

Factorise the following numbers into primes.
(i) 32
(ii) 57
(iii) 23
(iv) 150
(v) 216
(vi) 208
(vii) 765
(viii) 342
(ix) 377
(x) 559

Answer 1

(i)
32 = 2 × 16
= 2 × 2 × 8
= 2 × 2 × 2 × 4
​= 2 × 2 × 2 × 2 × 2
(ii)
57 = 3 × 19
(iii)
23 = 23 × 1
(iv)
150 = 2 × 75
= 2 × 3 × 25
​= 2 × 3 × 5 × 5
(v)
216 = 2 × 108
= 2 × 2 × 54
= 2 × 2 × 2 × 27
= 2 × 2 × 2 × 3 × 9
= 2 × 2 × 2 × 3 × 3 × 3
(vi)
208 = 2 × 104
= 2 × 2 × 52
= 2 × 2 × 2 × 26
= 2 × 2 × 2 × 2 × 13
(vii)
765 = 3 × 255
= 3 × 3 × 85
= 3 × 3 × 5 × 17
(viii)
342 = 2 × 171
= 2 × 3 × 57
= 2 × 3 × 3 × 19
(ix)
377 = 13 × 29
(x)
559 = 13 × 43