SOLUTION: A newly hired accountant takes 3 times as long to complete a tax return than an experienced accountant. If both accountants working together can complete the tax return in 70 minut

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Question 761002: A newly hired accountant takes 3 times as long to complete a tax return than an experienced accountant. If both accountants working together can complete the tax return in 70 minutes, how long would it take each accountant to complete the tax return alone? I tried this equation, not sure if I'm correct? 1/3x+1/x=70?
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The simple additivity of the accountants rates seems dubious, but we can still try to apply it.

Look at rates in jobs per minute.
New accountant rate: 1/(3x) jobs per minute
Experienced accountant rate: 1/x jobs per minute
Obviously, x is for how many minutes for the experienced accountant to do 1 job.

Both working together do 1 job in 70 minutes. Now, let us apply this additivity of rates for when both accountants work at the same time:
highlight%281%2F%283x%29%2B1%2Fx=1%2F70%29
The rate of BOTH accountants together, again, is {1 job} / {70 minutes}.

The key idea is {Rate}*{Time}={Quantity}
and the dimensions of Rate are Quantity per Time, or Quantity%2FTime.