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Question
Hello:

If 20 men can paint 5 houses in 10 days, how many days can 40 men paint 15 houses?

If the rate of 20 men per 5 houses is used 20 men/5 houses What is the calculation for determining the answer? 20 men/5 houses is a rate of 4 men per 1 house or 4 men/1 house in 10 days. I think this now becomes 0.4 of a man men per house per day. Am I correct so far? I'm not sure what to do next to determine the answer.

I thank you for your assistance.

Following is the reason:

Yes, 0.4 man per house per day....but what is the question being asked?

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How do I use the above rate (0.4 man per house per day) to determine the answer?

Sorry, I did not notice the original question.  I need to revise my previous answer.

Let's look at from another point of view.
20 men can paint 5 houses in 10 days = 1 man can paint 5/20=1/4 of a house in 10 days
= 1 man can paint 1/40 of a house per day.  Thus, 40 men can paint 40(1/40)=1 house per day.

So, 40 men would need 15 days to paint 15 houses.

Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Thanks for the reply!

Word Problems

Volunteer

Abe Mantell

Expertise

Hello, I am a college professor of mathematics and regularly teach all levels from elementary mathematics through differential equations, and would be happy to assist anyone with such questions!

Experience

Over 15 years teaching at the college level.

Organizations
NCTM, NYSMATYC, AMATYC, MAA, NYSUT, AFT.

Education/Credentials
B.S. in Mathematics from Rensselaer Polytechnic Institute
M.S. (and A.B.D.) in Applied Mathematics from SUNY @ Stony Brook