Question

John was 40" tall in 2008 and 46" tall in 2010. Dave was 53" tall in 2003 and 70" tall in 2007. Who is growing at

a faster rate? If each person keeps growing at the same rate, how tall can we expect each to be in 2011? Is this
a reasonable expectation?

Answer 1

John is growing at a faster rate.

Explanation:

John grew 6 inches in 2 years, while Dave grew 7 inches in 4 years. We can expect John to grow another 3 inches by 2011, making John 49 inches tall in 2011. We can expect Dave to grow about another 7 inches by 2011, since another 4 years has passed. This seems reasonable enough...