Lisa and Jen left home at the same time, only Lisa biked to school at a speed of 10 mph while Jen just walked at a speed of 4 mph.

How much time did it take Lisa to get to school if she reached school when Jen still was 1 mile away from it?

It took Lisa 10 minutes to get to school while Jen was 1 mile away from it.

Step-by-step explanation:

Step 1; First we must find out how much distance Lisa and Jen cover in a period of time. Lisa travels at 10 mph while Jen travels at 4 mph. So Lisa travels 10 miles in an hour which translates to 0.833 miles every 5 minutes. Meanwhile, Jen travels 4 miles in an hour which is 0.33 miles every 5 minutes.

Step 2; We have to find a period in time in which the difference between their distances covered is 1 mile. By calculating the distances every 5 minutes we get that Lisa covers 0.833 miles in 5 minutes, 1.666 miles in ten minutes and so on while Jen travels 0.333 miles in 5 minutes, 0.667 miles in 10 minutes and so on.

Step 3; In this scenario, at ten minutes Lisa traveled 1.666 miles while Jen travels 0.666 miles. The difference between these two is exactly one mile. So Lisa will reach school 10 minutes after leaving whereas Jen reaches 25 minutes after leaving.