Jimmy and his family  are  on their way to visit some family friends who live 780 miles away from them. based on the route they chose, they expect to complete their trip in three days. the distances and average speeds for the first two days driven are shown below. • first day: 4 hours at an average speed of 60 miles per hour • second day: 6 hours at an average speed of 65 miles per hour if the average speed on the third day is 60 miles per hour, how many more hours will it take for them to reach their family friends’ home?

The hours it take to reach their family's friend home is 2.5 hours

Step-by-step explanation:

The distance the family is expected to cover is 780 miles.  They expected to cover that distance within 3 days. Let us divide the trip into 3 sections.

Day 1

speed = distance/time

time = 4 hrs

speed = 60 miles per hr

distance = speed × time = 4 × 60 = 240 miles

Day 2

speed = distance/time

time = 6 hrs

speed = 65 miles per hr

distance = speed × time = 6 × 65 = 390 miles

Day 3

speed = distance/time

time = ?

speed = 60 miles per hr

distance = 780 - 240 - 390 = 150  miles

time  = distance/speed

time = 150/60

time = 2.5

The hours it take to reach their family's friend home is 2.5 hours

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,