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Itachi
May18-04, 03:56 PM
The sum of two positive integers is 9. What is the least possible sum of their recipricols?

matt grime
May18-04, 04:17 PM
you can do it by listing all the possibilities, that'll show you what the general pattern is.

mathman
May18-04, 04:59 PM
1/4 + 1/5. The general formala simply says make the numbers as equal as possible.

quddusaliquddus
May18-04, 05:05 PM
Oh man! ... mathman..I italic[jus] worked that out!!!...was about to post it!..oh well...:D

Gokul43201
May20-04, 11:42 PM
The sum of two positive integers is 9. What is the least possible sum of their recipricols?

OR "given the perimeter of a rectangle, how do you maximize its area?"

HallsofIvy
May21-04, 05:32 AM
A square with each side of length perimeter/4.

robert Ihnot
Jun30-04, 02:54 AM
I guess you could write 1/x + 1/(9-x) =s, differentiate and set equal to zero getting:

x^2 = (9-x)^2. The maximal value is x=0, and the minimal value is x=4.5, or they are the same. So 4 and 5 are the closest.