contestada

Betty is three times as old as her son now. In 12 years, Betty's age will be three years less than twice her son's age. How old is Betty's son now?

Respuesta :

Answer:

Betty is 27. Her son is 9.

Step-by-step explanation:

We will use b to represent Betty's age. We will use s to represent her son's age.

This year:

b = 3s

In 12 years' time:

b + 12 = 2(s + 12) - 3

b + 12 = 2s + 24 - 3

b + 12 = 2s + 21

b = 2s + 9

We know that b = 3s, so we can substitute this value into our equation.

3s = 2s + 9

s = 9

b = 3 x 9

b = 27