Question

The ratios of the number of the males to the number of females in a club are $7:4$. If there are $84$ males in a club, the total number of members in the club are-
A.$126$
B.$132$
C.$136$
D.$148$

Answer 1

Hint: Identify the known and unknown ratios and set up the proportion and solve accordingly. In these ratio types of questions, take any variable(x) as the reference number.

Complete step-by-step answer:
Given that: The ratios of males to the females are $7:4$
The number of males/ the number of females $ = \dfrac{7}{4}$
Let us suppose “x” is the common factor in both males and females.
Therefore, the total number of males $ = 7x$
 And, the total number of females $ = 4x$
Also, given that there are $84$ males in the club.
 $\begin{array}{l}
7x = 84\\
 \Rightarrow x = \dfrac{{84}}{7}\\
 \Rightarrow x = 12
\end{array}$
Therefore, the total number of females$ = 4x$
Put, $x = 12$
 $\begin{array}{l}
\therefore 4x = 4(12)\\
\therefore 4x = 48
\end{array}$
Therefore, the total female members $ = 48$
Total number of members in the club total number of male members total number of female members
Total number of members in the club $ = 84 + 48$
Total number of members in the club $ = 132$
This is the required answer.
Hence, option B is the correct answer.

Note:When solving these types of questions, do not find the value of x and leave the answer there, find the further values too.In this case,it is 7x and 4x