Question

The HCF of 120 and 150 is _____.

• A. 10
• B. 25
• C. 30
• D. 50

Answer 1

The correct option is C 30

Using common division method we get:

$\begin{array}{cc}2& 120,150\\ 5& 60,75\\ 3& 12,15\\ & 4,5\end{array}$

Since there are no common factors for 4 and 5 we cannot factorise the numbers any further.

Hence the HCF of 120 and 150 is
$2\times 5\times 3=30$