Andy, Bert and Calvin worked together repairing Andy's car. Bert worked twice as many hours as Calvin and Andy worked six hours more than Bert.

Question

Altogether they worked 51 hours. How many hours did Andy work?

Answer 1

You need to first identify what your equation is going to be.

You know from the problem that Bert worked twice as many hours as Calvin, so you can write this as 2C

Andy worked six hours more than Bert so you could write this as 6+B.

We don't know the number of hours that Calvin worked so we will leave him as C.

Bert=2C

Calvin=C

Andy=6+B

*If you notice Andy is the only semi equation that doesn't have the same variable. We will change it to look like this: 6+2C

Now you put each part together as an equation:

2c+c+6+2c=51

Now you solve. Combine like terms

5c+6=51

-6 -6

5c= 45

divide both sides by 5

c=9

In order to find out how many hours Andy worked, you need to find out how many hours Bert works. We found out that C=9 so we know that Calvin worked 9 hours.

Bert's formula:2c We will plug in 9 in for c=2(9)=18

Bert worked 18 hours

Andy worked 6 hours more than Bert, so we add 6 to Bert's 18 hours and get=24

Calvin=9

Bert=18

Andy=24

If you add all these numbers together you get 51.