how do i solve this math problem

Question

Terance galloped 12 miles in 40 minutes. Then he trotted 2 miles in 40 minutes. By how much did his first rate exceeded his second rate?

Answer 1

Trance's galloping rate is:

 

Rate₁ = (12 miles)/(40 minutes) = 3/10 mile per minute

 

His trotting rate is:

 

Rate₂ = (2 miles)/(40 minutes) = 1/20 miles per minute

 

His first rate exceeded his trotting rate by:

 

Rate₁ - Rate₂ = 3/10 - 1/20 = 6/20 - 1/20 = 5/20 = 1/4 mile per minute