Ordered pairs

Find the number of ordered pairs of positive integers (m,n) satisfying mâ‰¤ 2n â‰¤60 ,n â‰¤2mâ‰¤ 60

4 Answers

draw teh XY plane

draw the line x<=2y
and y<=2x

and the square given by lines x<=30 and y<=30

I hope that will help you :)

I tried to do by your method.But the number of points are very large.How to count them ?

fix a value of x and then count no of values of y such that

y/2<=x<=2y

Now find the summation :)

Thank you
:-)

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