Question

The fourth proportional to 2, 3, 4 is

• A. 5
• B. $\frac{2}{3}$
• C. 6

Answer 1

The correct option is C 6

Let $x$ be the required fourth proportional.
So, 2, 3, 4 and $x$ are in proportion.
Recall that the rule of proportion states that the product of extremes equals the product of means.
$\Rightarrow 2\times x=3\times 4$
$\Rightarrow 2x=12$
$\Rightarrow x=\frac{12}{2}=6$
Thus, the fourth proportional to 2, 3, 4 is 6. In other words, 2, 3, 4 and 6 are in proportion.