Problema Solution

Bob can type 2 letters in 4 hours while Bill can do it in 6 hours. How many hours would it take them to type six letters together?

Answer provided by our tutors

Bob's rate is: 2/4 = 1/2 letter per hour

Bill's rate is: 2/6 = 1/3 letter per hour

Let 'x' represent the hours they need to type 6 letters alone.

The together rate is: 6/x letters per hour

Now we can write:

1/2 + 1/3 = 6/x

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click here to see the equation solved for x

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x = 7.2 hr

x = 7 hr 0.2*60 min

x = 7 hr 12 min

Bob and Bill can type 6 letters in 7 hours and 12 minutes.