Answer:
Part A) 2 hours
Part B) d/60 hours
Part C) 48 miles/hour
Step-by-step explanation:
Part A) Let "d" be the distance in miles the family traveled to visit their relatives. How many hours did it take to drive there?
we know that
Let
x ----> the time it take on their way to visit relatives in hours
y ---> the time it take on the way back in hours
we know that
The distance of the way to visit is equal to the distance of the way back
The speed multiplied by the time is equal to the distance
so
60x=40y -----> equation A
y=x+1 -----> equation B
substitute equation B in equation A and solve for x
60x=40(x+1)
60x=40x+40
20x=40
x=2 hours
Find the value of y
y=2+1=3 hours
d=60x
The time it take on their way to visit relatives is 2 hours
The time it take on the way back is 3 hours
Part B) In terms of "d," how many hours did it take to drive there?
we have that
The distance is equal to the speed multiplied by the time
d=60x
Solve for x
x=d/60 hours
Part C) Write and solve an equation to determine the distance the family drove to see their relatives. What was the average rate for the entire trip?
To find the average rate for the whole trip we will need the total distance and the total time
The distance of the way to visit is
d=60x
substitute the value of x
d=60(2)=120 miles
so
The total distance is
120(2)=240 miles
we know that the total time is
2 + 3 =5 hours
The average rate for the complete trip is
240/5=48 miles/hour
