Starting at home jessica traveled uphill to the toy store for 12 minutes at just 10 mph. she then traveled back home along the same path downhill at a speed of 30 mph. what is her average speed for the entire trip from home to the toy store and back?

15 miles per hour

Step-by-step explanation:

Average Speed is:

Average Speed = Total Distance/Total Time

Going uphill, she took 12 minuets, that is hours is 12/60 = 0.2 hours

We know D = RT, Distance = Rate(speed) * Time

Thus,

D = 10mph * 0.2 hr = 2 miles

So, total distance (uphill and downhill) = 2 + 2 = 4 miles

Downhill the time she took is

D = RT

2miles = 30mph * T

T = 2/30 = 1/15 hours = 1/15 * 60 = 4 minutes

Hence total time is 12 + 4 = 16 minutes

Note: 16 minutes = 16/60 = 4/15 hours

Now

Average Speed = Total Distance/Total Time

Average Speed = 4 miles/ 4/15 hours = 15 mph