Two beauticians, Lydia and Jackie, are working on your hair. Lydia can complete the work in 2 hours, while Jackie can complete the work in 1 hour. How many hours do the beauticians take if they work together?

Question

anonymous · Answer

@phi

anonymous · Answer

I also need this one.

phi · Answer

You could think of these problems as  rate * time = job

rate is "jobs per hour", and time is hours
 Lydia can complete the work in 2 hours... that means Lydia's rate is 1 job/2 hours

anonymous · Answer

The choices for the first question are:
-1/2 
-3/2
-2/3
-4/3

anonymous · Answer

I tried to solve it but I got 1...

potatoes.ramu · Answer

I don't know how to do this, I'm so sorry :(

phi · Answer

Jackie can complete the work in 1 hour means Jackie's rate is 1 job per 1 hour or 1 job/hour

anonymous · Answer

so 1/2 + 1/1

anonymous · Answer

1/2 + 1/1= 1/x

anonymous · Answer

I know *how* to do it. it's just that I got a whole number instead of a fraction

phi · Answer

If you do rate * time  for both of them:
$$\left( \frac{1}{2}+ 1\right) t = 1 \text{ job}$$

anonymous · Answer

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