Joe went to see his Grandmother. He promised his Grandma that he would arrive at her house at 5 pm. He leaves his house at 3:00 and this will allow him 2 hours to get to her house. Joe will need to travel 70 miles to get to her house. How fast will Joe need to drive to make it to Grandma's house on time?

35 mph

Explanation:

From the question given above, the following data were obtained:

Time (t) = 2 hours

Distance (d) = 70 miles

Speed (S) =.?

Speed is simply defined as the distance travelled per unit time. Mathematically, it is expressed as:

Speed (S) = Distance (d) / Time (t)

S = d/t

With the above formula, we can calculate how fast (i.e the speed) Joe will need to drive to make it to his Grandma's house on time. This can be obtained as follow:

Time (t) = 2 hours

Distance (d) = 70 miles

Speed (S) =.?

S = d/t

S = 70/2

S = 35 mph

Therefore, Joe will drive at 35 mph in order to get to his Grandma's house on time.

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