Question

The monthly salary of $A,B$ and $C$ are in the ratio 2:3:5. If $C's$ monthly salary is Rs.1200 more than that of $A$, find $B's$ monthly salary.
A. Rs.2000
B. Rs.1000
C. Rs.1500
D. Rs.1200

Answer 1

Hint: We will begin by letting the common factor of the ratio be $x$. Then, write the salary of $A,B$ and $C$ in terms of $x$. Next, form the equation according to the given condition. Solve the equation to find the value of $x$. At last, substitute the value of $x$ in the expression of the monthly salary of $B$ to get the required answer.

Complete step-by-step answer:
We have been given that the ratio of salary of $A,B$ and $C$ is 2:3:5
Let the common factor of the ratio be $x$
Then, the salary of $A$ is $2x$, salary of $B$ is $3x$ and the salary of $C$ is $5x$.
Now, according to the given condition, the monthly salary of $C$ is 1200 more than the salary of $A$.
 $5x = 2x + 1200$
Bringing $2x$ to LHS and solving it further,
$
  5x - 2x = 1200 \\
   \Rightarrow 3x = 1200 \\
$
On dividing the equation throughout by 3, we will get,
$x = 400$
Now, we will substitute the value of $x$ in the expression of monthly salary of $B$.
Thus, the salary of $B$ is $3\left( {400} \right) = 1200$
Hence, option D is correct.

Note: Ratio shows comparison between objects. It shows how many times one number contains the other. The order of the ratio plays an important role. In this type of questions, the formation of the equation should be according to the given condition to avoid mistakes.