Question

Sofia is 38 years old. Write an equation that relates Sofia's age to Tony's age, t. How old is Tony?

(Sofia’s age is 2 times the combined ages of Carlos and Lily - Carlos’s age is 4 more years than Tony’s age - and Lily’s age is one more than 6 times Tony’s age)

Answer 1

Let s, c, y and t represent the ages of Sofia, Carlos, Lily and Tony respectively.

c + y = 2s ------ equation (1)

t + 4 = c ------ equation (2)

6t + 1 = y ------ equation (3)

Since Sofia is 38 years old, substitute s = 38 into equation (1):

c + y = 2(38)

= 76 ------ equation (4)

Substitute equations (2) and (3) into equation (4):

t + 4 + 6t + 1 = 76

7t + 5 = 76

7t = 71

∴ t = 10 (to the nearest whole number)

∴Tony is 10 years old (to the nearest whole number).