Question

Bill spends two days driving from Point A to Point B . On the first day, he drove 2 hours longer and at an average speed 5 miles per hour faster than he drove on the second day. If during the two days he drove a total of 680 miles over the course of 18 hours, what was his average speed on the second day, in miles per hour?

Answer 1

average speed on the second day is 35 mph

Step-by-step explanation:

given data

time = 2 hour

speed = 5 miles per hour

total distance = 680 miles

total time = 18 hours

to find out

average speed on the second day

solution

according to question

day 1 , he drive 2 hour longer

so we consider x hours driving on day 2

so on day 1 he drive x + 2

so

we can say total drive = 18 hours that mean

18 = x + (x + 2)

so that x = 8

so we say

day 1 he drive = (8+2) = 10 hours

and day 2 he drive = 8 hours

and

now we consider day 2 speed = x

so day 1 speed will be = x + 5

and

we know that total distance = 680

and distance = speed × time

so we say

680 = x (8) + ( x + 5 ) (10)

680 = 18 x + 50

so x = 35

so that average speed on the second day is 35 mph