Question

Mrs. Simpson drove 105 miles in 2 1/2 hours. What was Mrs. Simpson's average speed in miles per hour?

Answer 1

the answer is 42.You get this when you divide 105 by 2 1/2

Answer 2

105 m = 2.5 h

x miles = 1 hour

You cross multiply since it's a proportion:
2.5 * x
105 * 1

=

2.5x = 105

Then you divide everything by 2.5

The answer is 42