Question

Jacks age is three years more than twice the age of his younger brother jimmy if the sum of their ages is at most 18 find the greatest age that jimmy could be ???

Answer 1

eg. x is Jack's age, y is Jimmy's age

x = 3 + 2y
x + y = 18

Subtitute x with 3 + 2y
x + y = 18
3 + 2y + y = 18
3 + 3y = 18
3y = 18 - 3
3y = 15
y = 15/3
y = 5

Jimmy's age is 5

Answer 2

5 is the correct answer.
To prove it, subtract 5 from 18 - You'll get 13.
5 x 2 + 3 = 13.