Question

shrutee is 10 years old and her mother is 38 years old.after how many years, age of shrutee's mother will be 3 times her age?

Answer 1

s = 10y, m = 38y
let their ages when mother is 3 times shrutee's age be 10 + x and 38 + x
the difference between their ages = 38 - 10 = 28y
3(10 + x) = 38 + x
30 + 3x = 38 + x
3x - x = 38 - 30
2x = 8
x = 4
therefore shrutee will be ⅓rd her mother's age after 4 years.

verification:
10 + 4 = 14; 38 + 4 = 42
3(14) = 42