x, y and z

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x, y and z

by shibal » Sat May 16, 2009 12:33 pm
If x, y and z are positive intergers and 3x=4y=7z, then the least possible value for x+y+z?

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Re: x, y and z

by dtweah » Sat May 16, 2009 1:45 pm
shibal wrote:If x, y and z are positive intergers and 3x=4y=7z, then the least possible value for x+y+z?

OA: 61
What is LCM of 3 4 7? 84
3 x28=4x 21=7 x 12
28+21+12=61

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by artistocrat » Sat May 16, 2009 2:51 pm
3x=4y=7z

3*(4*7)=4*(3*7)=7*(3*4)

3*28=4*21=7*12

so, x=28, y=21, z=12

then, x+y+z=61