Question

9. Find the common factors of a) 25 and 75 b) 20 and 28 ​

Answer 1

Answer:

GCF of 20 and 28 by Prime Factorization

GCF of 20 and 28 by Prime Factorization Prime factorization of 20 and 28 is (2 × 2 × 5) and (2 × 2 × 7) respectively. As visible, 20 and 28 have common prime factors. Hence, the GCF of 20 and 28 is 2 × 2 = 4.

Step-by-step explanation:

Answer 2

Answer:

a)25

b)4

Step-by-step explanation:

a) 25= 5×5

25=5²×3⁰

75= 5×5×3

75= 5²×3¹

HCF= 5²×3⁰

= 25×1

= 25

b) 20= 2×2×5

20= 2²×5¹×7⁰

28= 2×2×7

28= 2²×5⁰×7¹

HCF = 2²×5⁰×7⁰

= 4×1×1

= 4