Question

Which expression is not equivalent to the expression $?$

$72m-60$

• A. $6(12m-10)$
• B. $4(18m-15)$
• C. $12m$
• D. $12(6m-5)$

Answer 1

Answer: (C), (D)

$12(6m-5)$

Step 1 : Finding the common factor

Given expression, $72m-60$
So, the factors of $\left(72m\right),\left(60\right)$

$$\begin{gathered} 72m=2\times 2\times 3\times 3\times 2\times m \\ 60=2\times 2\times 3\times 5 \end{gathered}$$

We can see that the G.C.F of $\left(72m\right),\left(60\right)$ is $2\times 2\times 3=12$

Step 2 : Simplifying the expression

$$\begin{gathered} \Rightarrow 72m-60=12\left(6m\right)-12\left(5\right) \\ =12(6m-5) \end{gathered}$$

Option (c) is not equivalent to the given expression

Hence, correct option is (c).