Seth is
q years old. Bobby is five times as old as Seth and Jack is 4 years younger than Bobby.
- Express Jack's age in terms of q.
- Seth is 9 years old as of now. ln how many years' time will Jack be 3 times as old as Seth?
(a)
Seth's age =
q years
Bobby's age = 5
q years
Jack's age = (5
q - 4) years
(b)
q = 9
Difference in age remains unchanged.
Difference in age between Jack and Seth
= (5
q - 4) -
q = 5
q -
q - 4
= 4
q - 4
= 4 x 9 - 4
= 32 years
Difference in the age when Jack will be 3 times as old as Seth
= 3 u - 1 u
= 2 u
2 u = 32
1 u = 32 ÷ 2 = 16
Number of years' time so Jack will be 3 times as old as Seth
= 16 - 9
= 7 years
Answer(s): (a) (5
q - 4) years; (b) 7 years
