Question

Find the HCF and LCM of 12, 15 and 20, by prime factorization method.

Answer 1

$$\begin{gathered} \mathrm{The}\mathrm{prime}\mathrm{factorisation}\mathrm{of}12,15\mathrm{and}20\mathrm{are}; \\ 12=2\times 2\times 3 \\ 15=3\times 5 \\ 20=2\times 2\times 5 \\ \mathrm{So},\mathrm{LCM}=2\times 2\times 3\times 5=60 \end{gathered}$$