mechanic to install carburetors in 5 cars?

A.) 6 hours 20 minutes

B.) 6 hours 40 minutes

C.) 7 hours 15 minutes

D.) 7 hours 40 minutes

E.) 7 hours 45 minutes

3 cars 5 cars

--------- = ------------ {set up a proportion}

4 hours x hours

3x = 20 {cross-multiplied}

x = 20/3 {divided both sides by 3}

x = 6 2/3 {changed to mixed number}

x = 6 hours 40 minutes {2/3 of an hour is 40 minutes}

**B.) 6 hours 40 minutes**

*- Algebra House*