SOLUTION: if one person takes 30 min to paint a room and another person takes 45 min how long would it take if they did it together.
what formula would I use to solve this?
Algebra ->
Rate-of-work-word-problems
-> SOLUTION: if one person takes 30 min to paint a room and another person takes 45 min how long would it take if they did it together.
what formula would I use to solve this?
Log On
Question 256460: if one person takes 30 min to paint a room and another person takes 45 min how long would it take if they did it together.
what formula would I use to solve this? Found 2 solutions by unlockmath, solver91311:Answer by unlockmath(1688) (Show Source):
You can put this solution on YOUR website! Hello,
Let's represent the amount of time the can both do it with "x". Then 1/x will show which both can do.
We'll show one person doing the work as 1/30 and the other as 1/45. We can add these and it will equal 1/x shown like this:
1/30 + 1/45 = 1/x Now multiply by 90x will give us:
3x + 2x = 90 combine like terms will be:
5x=90 Divide both sides by 5
x=18
So it will take 18 minutes if both work together.
Make sense?
RJ
Check out a new math book at
www.math-unlock.com
If A can do a job in x time periods, then A can do of the job in 1 time period. Likewise, if B can do the same job in y time periods, then B can do of the job in 1 time period.
