Maura drives to work, a distance of 30 miles in 40 minutes. she takes the same route to return home. if her average speed on the trip home is half as fast as her average speed on the trip to work, what is her average speed, in miles per hour, for the entire round trip

Well to solve this firstly we should calculate her average speed while she was going to work. Which comes out to be 45 miles per hour.

Now if her average speed while going home is half as fast as while coming to work was, the answer would be 22.5 miles per hour. So the average speed for the total journey would be the average for these two values. As the distance was same for both the journeys we can simply do 45 + 22.5 / 2 = 33.75 mph.

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2