problem: sue can sew a dress in 5 hrs; helen, in 3....

[jjen1978]

sue can sew a precut dress in 5 hours. Helen can sew the same dress in 3 hours. If they work together, how long will it take them to complete sewing that dress? Give you answer rounded to one decimal place, if necessary.

 

[tkhunny]

Not clear at all. It depends on how much Helen can sew while Sue is cutting.

 

[stapel]

It depends on how much Helen can sew while Sue is cutting.

The exercise specifies that the seamstresses are provided with precut pieces, doesn't it? Or am I misreading that?

In any case, one usually makes the (unrealistic) assumption that the workers in no way interfere with each other, that their labors are strictly additive.

Eliz.

 

[tkhunny]

Oh, I see. I thought Sue was just cutting. I missed that they were sewing the same dress under the same conditions.

Well, jjen1978, standard setup.

x = the time working together.

1/5 + 1/3 = 1/x

Solve for x and it had better be less than 3.