Answer:
The speed of the truck is 42 mph
Step-by-step explanation:
we know that
The speed is equal to divide the distance by the time
Let
s -----> the speed in miles per hour
d ----> the distance in miles
t ----> the time in hours
[tex]s=\frac{d}{t}[/tex]
[tex]d=s(t)[/tex]
step 1
Find out the distance traveled by the car at 7:00 P.M
we have
[tex]s=46\ \frac{mi}{h}[/tex]
[tex]t=7:00 P.M-4:00 P.M=3\ h[/tex]
[tex]d=s(t)[/tex]
substitute the values
[tex]d=46(3)=138\ mi[/tex]
step 2
Find out the speed of the truck
we know that
At 7:00 P.M the distance is equal to
[tex]d=264-138=126\ mi[/tex]
[tex]t=7:00 P.M-4:00 P.M=3\ h[/tex]
substitute
[tex]s=\frac{126}{3}[/tex]
[tex]s=42\ \frac{mi}{h}[/tex]