Question

Find the value of 𝑥 in each of the following such that the given numbers are in proportion.

(i) $14,42,$ x and $75$.

Answer 1

Step : calculate the value of $x$
Given numbers are $14,42,x$ and $75$.
If $14:42$ is equal to $x:75$ then they are in proportion.
Therefore we can find out the value of $x$ as follows:

$14:42=x:75$
$\Rightarrow 14\times 75=x\times 42$
($\because$ Product of extremes = product of means)

$\Rightarrow x=\frac{14\times 75}{42}$
$\Rightarrow x=\frac{7\times 2\times 15\times 5}{7\times 6}\Rightarrow x=\frac{2\times 3\times 5\times 5}{2\times 3}$
$\therefore x=25$
Hence, the value of $x$ is $25$.