Number Theory/Rates



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

Can the answer be determined by using the follow rate?

20 men/5 houses is a rate of 4 men per 1 house or 4 men/1 house in 10 days.  This now becomes 0.4 of man men per house per day.  I'm not sure what to do next to determine the answer.

I thank you for your reply.

I think I have been over this with you before.
The number of houses is jointly proportional to the number of men and the number of days.
So h = kmd.  Substituting the given gets you to k = 1/40.  So h = md/40 and d = 40h/m.  When m=40 and h =15, d =15.
Best wishes


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