Question

In the given question, 2 years back the age of Sushil's father was 7 times Sushil's age then. If the sum of their present age is 36 years, what is the age of Sushil's father at present?
A. 28
B. 30
C. 40
D. None of these

Answer 1

Hint: In order to solve this problem we have to assume variables and make equations according to the question provided.

Complete step-by-step answer:

Let the present age of Sushil be x years.
Then, present age of his father =(36−x) years…………………(1)

According to question 2 years back, Sushil's age =(x−2) years
and Father's age =(36−x)−2 years =(34−x) years

Given, (34−x)=7(x−2)
$ \Rightarrow $34−x=7x−14
$ \Rightarrow $34+14=7x+x
$ \Rightarrow $8x=48
$ \Rightarrow $x=6

On putting the value of x in equation (1) we get the age of Sushil’s father as:
$ \Rightarrow $36 - 6 =30 years.

Hence, the correct option is B.

Note: In such types of problems we should always try to assume the minimum number of variables possible. Then solving according to the question by making an equation you will get the right answer. The number of unknowns should always equal to or less than the number of equations with those unknowns.