4 years ago Ramu's age is the square root of his father's age. Now the age of Ramu and his father are in the ratio 1:4.Then what is Ramu's age?
A8
B10
C12
D40
Answer:
B. 10
Read Explanation:
4 years ago,
Ramu's age as x and his father's age is x².
Now, their ages are in the ratio 1:4, that is, after 4 years.
(x + 4) /(x² + 4)=1/4
x²-4x-12=0
x = 6
Ramu's age 4 years ago was 6. His fathers age was 36.
Now Ramu's age is 10 and that of his father is 40.
