Question

what is the ratio between the LCM and HCF of 15, 20, 25.​

Answer 1

$15 = 3 \times 5 \\ 20 = 2 \times 2 \times 5 \\ 25 = 5 \times 5 \\ hcf = 5 \\ lcm = 5 \times 3 \times 2 \times 2 \times 5 = 300 \\ so \: \: \: \frac{lcm}{hcf} = \frac{300}{5} = \frac{60}{1}$

hence ratio is 60:1