A mechanic can install carburetors in 3 cars every 4 hours. At
that rate, how long will it take the mechanic to install
carburetors in 5 cars?
A. 6 hr. 20 min.
B. 6 hr. 40 min.
C. 7 hr. 15 min
D. 7 hr 30 min
E. 7 hr. 45 min

B. 6 hr. 40 min

Step-by-step explanation:

In the question is it said that a mechanic can install carburetors in

3 cars = 4 hours

How long with it take of install carburetors in 5 cars

We have

3 cars = 4 hours

5 cars = X (unknown so we designated it as X)

We cross multiply

3X = 4× 5

3X = 20

Divide both sides by 3

Hence, we have

3X ÷ 3 = 20÷ 3

X = 6.667 hours

In other to convert 6.667 hours to proper time i.e in hours and minutes ,

We have

1 hour = 60 minutes

0.667 hours = y( unknown so we represent with y)

Cross multiply

y = 60× 0.667 hours

y = 40.02 mins.

Approximately ≈ 40 mins

Therefore we add 6 hours + 40 mins

= 6 hours 40mins

Therefore, will it take the mechanic 6 hours 40 minutes to install carburetors in 5 cars