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mehrasa
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if m,n are both two digit integers. and m-n=11x, is x an integer?
1) the tens digit and the unit digit of m are the same.
2) m+n is a multiple of 11.
Q is asking whether m-n is multiple 11 or not?
stat1) the stat give an information about one of the element (m). we do not have any info abt the another one (n) ==> not sufficient
stat2) we know that m+n=11x is true when m and n has the same digit but in reverse direction... for example 12 and 21... under this circumstance their substraction never divisible by 11 (but divisible by 9) ==> the answer to stat 2 is NO and it is sufficient
[spoiler]IMO:B[/spoiler]
what do you guys think?
1) the tens digit and the unit digit of m are the same.
2) m+n is a multiple of 11.
Q is asking whether m-n is multiple 11 or not?
stat1) the stat give an information about one of the element (m). we do not have any info abt the another one (n) ==> not sufficient
stat2) we know that m+n=11x is true when m and n has the same digit but in reverse direction... for example 12 and 21... under this circumstance their substraction never divisible by 11 (but divisible by 9) ==> the answer to stat 2 is NO and it is sufficient
[spoiler]IMO:B[/spoiler]
what do you guys think?
