Annie and her family are on their way to visit some family friends who live 820 miles away from them. Based on the route they choose, they expect to complete their trip in three days. The distances and average speeds for the first two days driven are show below. First day: 6 hours at an average speed of 60 miles per hour Second day: 4 hours at an average speed of 65 miles per hour If the average speed on the third day is 50 miles per hour, how many more hours will it take for them to reach their family friends home?

4 hours

Step-by-step explanation:

The distances and average speeds for the first two days driven are show below.

Step 1

We calculate the total distance covered in the first two days

First day: 6 hours at an average speed of 60 miles per hour

Hence:

1 hour = 60 miles

6 hours = x

x = 60 × 6

x = 360 miles

Second day: 4 hours at an average speed of 65 miles per hour

Hence:

1 hour = 65 miles

4 hours = x

x = 65 × 4

x = 260 miles

The distance covered for the first two days =

(360 + 260)miles

= 620 miles

Step 2

The total distance for the entire trip = 820 miles

Hence, the distance left to cover on the third day = (820 - 620)miles

= 200 miles

In the question, we are told:

If the average speed on the third day is 50 miles per hour,

The number of hours it will take for them to reach their family friends home is calculated using the formula

Time = Distance/Speed

Time = 200 miles/50 miles per hour

Time = 4 hours

i did it myself and i got 4.2 (b) hope its right

step-by-step explanation: