Question

Type the correct answer in each box. Use numerals instead of words. If necessary, use / for the fraction bar(s). John is five years older than his sister. The product of their present ages is 150. John's present age is years, and his sister's present age is years.

Answer 1

John's present age is 15 years.

His sister's present age is 10 years.

Step-by-step explanation:

step 1 :

Let,

• Age of sister = x
• Age of john = x+5

step 2 :

The product of their present ages is 150.

⇒ x(x+5) = 150

⇒ x^2 +5x -150 =0

step 3 :

Using factorization method,

product of the roots (-10$\times$15) = -150

Sum of the roots (-10+15) = 5

∴ The values of x are x=10 and x=-15.

Age cannot be negative.

So, the present age of sister is 10 years.

The present age of John = x+5 = 15 years.