Properties of numbers

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Re: Properties of numbers

by mohitsharda » Fri Sep 25, 2009 10:53 pm
heshamelaziry wrote:If Y is the smallest positive integer suvh that 3150 multiplied by Y is the square of an integer, then Y must be

2
5
6
7
14

Please explain
3150 = 2*7*225 = 2*7*(15^2)
3150 is a perfect square =>

y must have 2 and 7 as its factors.
Smallest possible value of y = 14

So, (E)
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Re: Properties of numbers

by heshamelaziry » Fri Sep 25, 2009 11:19 pm
mohitsharda wrote:
heshamelaziry wrote:If Y is the smallest positive integer suvh that 3150 multiplied by Y is the square of an integer, then Y must be

2
5
6
7
14

Please explain
3150 = 2*7*225 = 2*7*(15^2)
3150 is a perfect square =>

y must have 2 and 7 as its factors.
Smallest possible value of y = 14

So, (E)
Say i had 19 as the biggest number in the prime factors, would y be 2*19 ??????? In other words, why 7 ?????