Answers – Daniel is 13 years old; Ben is 33 years old
WORKINGS
Let Ben’s age be ‘x’ Let Daniel’s age be ‘y’
Given: Ben is 20 years older than Daniel x = y + 20 ….. (Equation I)
Given: Three years ago, Ben was 3 times as old as Daniel. x – 3 = 3(y – 3) ….. (Equation II)
Substitute ‘y + 20’ for x in Equation II x – 3 = 3(y – 3) (y + 20) – 3 = 3(y – 3) y + 20 – 3 = 3y – 9 y + 17 = 3y – 9 3y – y = 17 + 9 2y = 26 y = 13 Daniel is 13 years old ….. (Answer I)
Substitute 13 for the value of ‘y’ in equation I x = y +20 x = 13 + 20 x = 33 Ben is 33 years old ….. (Answer II)
