Jane can mow a lawn in 2 hours. Henry can mow the same lawn in 1.5 hours. About how long will it take to mow the lawn if Jane and Henry worked together?

Question

radar · Answer

Let us assume they each have their own lawn mower and they work as they have worked before.
1.  We know that with them both working together, the total time will be less than either one working along..
2.  Use the "product" over sum rule.

(2)(1.5) over 2 + 1.5
3/3.5 = .857 hr or 51.43 minutes

radar · Answer

Working together is like connecting resistors in parallel and calculating the total resistance.

anonymous · Answer

Awesome. Thanks Radar. I wish I could analyze word problems like that. I have the hardest time doing so and it drives me mad.

radar · Answer

Understand, my daughters had the same problem.  Give them an equation and they could work them.  But to set up an equation from written text, it was a PIA.

anonymous · Answer

How do you improve that? 
I have that exactly problem.  BTW I get your statement on resistors, currently in school for Electronics sadly and can't do simple math hahah.

radar · Answer

|dw:1415915132393:dw| or the same as
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