question_answer

Mr. Sohanlal is four times as old as his son. Four years later, the sum of their ages will be 43 years. The present age of the son is:

A) 5 years                

B)       7 years

C) 8 years                

D)        10 years

E) None of these

Correct Answer: B

Solution :

Explanation Option [b] is correct. Let the present age of the son be x years. Then, the age of Sohanlal would be 4x years. Four years later, their ages would be (x + 4) and (4x + 4) years, respectively. Now, as per the information given in the question, \[\left( x+4 \right)+\left( 4x+4 \right)=43\]. or      \[5x+8=43\] or      \[5x=35\] years or       \[x=7\]  years Therefore, the present age of the son is 7 years. Number of even numbers from 2 to 50 are 25. Number of odd numbers from 2 to 50 are 24. Number of prime numbers from 2 to 50 are 15.