Word problem dealing with rate. Solve for rate of variable.

[aifan]

Homework Statement

You run a small business making widgets. You have two employees. Employee A takes two times as long as employee B to make a widget. During each day, both employees working together will make 15 widgets, how many widgets get made by employee A each day?

Homework Equations

rate = area/time

The Attempt at a Solution

I know the answer is 5 but I don't understand why. Here is my attempt.

A = 2*B<--- A takes twice the time of B
B = B

since I am suppose to be solving for A write in terms of A
B = A/2

so their rate together should be A + B = 15 widgets.

A/2 + A/2 = 15and this is were I get stuck.

 

[dlgoff]

...their rate together should be A + B = 15 widgets.

What is A equal to?

 

[aifan]

A is equal to 2B.
I tries doing 2B + B = 15
which is 5 but that is solving for B not A

 

[dlgoff]

Well you know what A + B equals to. So A = ?

 

[aifan]

A = 15 - b

 

[dlgoff]

I guess we need A=1/2B (or B=2A) since were talking about how many widgets A can make compared to B.

Sorry about that.

 

[aifan]

But A takes longer than B it takes twice as long as B does so A would be 2*B right?
not the other way around?

 

[dlgoff]

But A takes longer than B it takes twice as long as B does so A would be 2*B right?
not the other way around?

No. A takes twice as long so only makes half as many widgets as B. You want widgets not time.

 

[aifan]

okay I got it now! I made a stupid error Thank you!

 

[dlgoff]

okay I got it now! I made a stupid error Thank you!

I made the same mistake.