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ranjitr303
Member since Nov-23-10
May-11-11, 01:36 PM (EST)    "divisibility"

 if (A + mX)/(5 or 10)is divisible by m, then A is divisible by m. also if (A - mX)/(5 or 10)is divisible by m, then A is divisible by m.eg. is 273 divisible by 7?ans; to obtain a number close to 273 that is divisible either by 5 or 10 , we can take X= 1 as m=7. then A+mX = 273+7*1=280 WHICH IS DIVISIBLE BY 10. THEREFORE 273 is divbisible by 7.ranjitr

alexb Charter Member
2806 posts
May-11-11, 01:38 PM (EST)    1. "RE: divisibility"
In response to message #0

 >if (A + mX)/(5 or 10)is divisible by m, then A is divisible >by m. >also if (A - mX)/(5 or 10)is divisible by m, then A is >divisible by m. >>eg. is 273 divisible by 7? >ans; to obtain a number close to 273 that is divisible >either by 5 or 10 , we can take X= 1 as m=7. then A+mX = >273+7*1=280 WHICH IS DIVISIBLE BY 10. You probably meant to say that 280 is divisible by 7, right?THEREFORE 273 is >divbisible by 7.

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