a family backpacking at Yosemite national park took 5 hours to climb a mountain trail 7.5 km long. what was the family's average speed

The average speed will be 1.5km/hr.

Explanation:

Distance need to be traveled = 7.5Km

Time taken = 5 hours

Average speed refers to total distance traveled with respect to total time taken.

It can be calculated as given below:

Average speed = total distance / total time taken

Substituting the values we get, as shown below

Average speed = 7.5/5=75/50

Average speed = 1.5 Km/hr