Question

Find the ages of John and Mary if four times John's age equals three times Mary's age, and Mary is ten years older than John.

Answer 1

M = J + 10

4J = 3M

Substitute J+10 for M in second equation and solve for J. Insert that value into the first equation and solve for M. Check by inserting both values into the second equation.

Answer 2

J= 120
M= 130