Question

Which of the following expressions represents the given model?

• A. $2(a+3b+4c)$
• B. $4(a+2b+3c)$
• C. $3(a+2b+4c)$
• D. $3(a+b+4c)$

Answer 1

The correct option is C $3(a+2b+4c)$

We can see that the variable $a$ appears three times, the variable $b$ appears $6$ times, and the variable $c$ appears $12$ times.
According to this, the expression will be $3a+6b+12c.$
On solving option a, we get:
$4(a+2b+3c)=4\times a+4\times 2b+4\times 3c)=4a+8b+12c$
On solving option b, we get:
$2(a+3b+4c)=2a+6b+8c$
On solving option c, we get
$3(a+2b+4c)=3a+6b+12c$
Therefore, the expression $3(a+2b+4c)$ represents the given model.