What is the average speed of a turtle in inches/minutes covering 250 inches in 2.5 hours?

1.6 inches/minute

Explanation

First, you must read through the problem carefully and notice the unites asked for and those that are offered as facts to use.  So, the time covered by the turtle is given in terms of hours.  But, the problem wants the solution to be in minutes.

So, convert the time unit first

time covered by turtle = 2.5 * 60 = 150 minutes

average speed of the turtle = distance in inches / time in minutes

                                                  = 250 / 150

                                                  = 1.6 inches/minute

Note: 100 inches/hour is correct and convertible to 1.6 inches/minute, but it is not what is the problem asking for