Question

Jerry is 50 inches tall growing at a rate of 1/24 inches per month. Adam is 47 inches tall growing at a rate of 1/8 per month. If they continue to grow at these rates for the next 4 years in how many months will they be the same height? Solve two different ways and show solution processes

Answer 1

Jerry-height = 50 + (1/24)m
Adam-height = 47 + (1/8)m

they have the same height when ...

50 + m/24 = 47 + m/8
3 = m/8 - m/24
m/12 = 3
m = 36

or, from

50 + m/24 = 47 + m/8
multiply each term by 24 to get rid of fractions
1200 + m = 1128 = 3m
72 = 2m
m = 36