Question

Choose the correct option ?

If the first, second, and fourth terms of a proportion be $16,24$ and $54$respectively, then its third term is :

• A. 32
• B. 48
• C. 36
• D. 28

Answer 1

The correct option is C

36

Let the third number be = $x$

These numbers are in proportion so the product of extremes = product of means (when four numbers are given then first and fourth number are called extremes and second and third numbers are called means)

$16,24,x$ and $54$are in proportion

$$\begin{gathered} 16\times 54=24\times x \\ \frac{16\times 54}{24}=x \\ \sout{\frac{\sout{16}\times 54}{\sout{24}}}=x \\ \sout{\frac{2\times \sout{54}}{\sout{3}}}=x \\ 2\times 18=x \\ 36=x \end{gathered}$$(after cancelling by 8)

Therefore value of x=36