help i have a test over this tomorrow and i dont get it!!!!!

[cmw11]

What is the formula to solve this or the order of operations?


If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa, and Tom worked together to complete it?

 

[Loren]

I'll do a similar problem.

It takes A 4 hours to paint a room.
It takes B 6 hours to paint the same room.
How long will it take to paint the room if they work together.
Solution.
Name stuff and write it down.
Let x represent the time it takes to paint the room if they work together.

In 1 hour A can paint 1/4 the room.
In 1 hour B can paint 1/6 of the room.
In 1 hour working together they can paint 1/x of the room.
\(\displaystyle \frac{1}{4}+\frac{1}{6}=\frac{1}{x}\)
Solve for x. There's the answer.

 

[Denis]

What is the formula to solve this or the order of operations?

What makes you think there is a formula?

What is your understanding of "order of operations"?

 

[stapel]

What is the formula to solve this or the order of operations?

There is no one "formula" for this sort of exercise, but there is a general technique (which they were supposed to have taught you!). To learn it now, try here.

To learn about the order of operations, try here.

Good luck on your test!