if m and n are both positive integers and m>n , is 6 a factor of the product mn?
1.m+n=188
2.m is 150% of n
mn problem
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- pradeepkaushal9518
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Examine (1); 1 + 187 = 188
187 * 1 = 187
187 / 6 = 31 + 1/6
But,
186 + 2 =188, so
186 * 2 = 372, and
372 / 6 = 62
So, (1) is insufficient.
(2) say that m = 1.5n, so
Because we know that m and n must b integers we can say that the very minimum m and n could be is,
m=3, n=2, 3=1.5*2
The astute observer would also note at this point that any other combination of m and n will be multiple of m and n. We can say that the ratio is
3m:2n
More importantly we can see,
[spoiler]3m*2n=6mn[/spoiler]
Thus any combination of m and n is going to result in a multiple of six (because we're multiplying any combination by 6. Thus (2) is sufficient.
The answer is B.
Could you please confirm that B is the OA?
Hope this helps.
Thanks,
Jared
187 * 1 = 187
187 / 6 = 31 + 1/6
But,
186 + 2 =188, so
186 * 2 = 372, and
372 / 6 = 62
So, (1) is insufficient.
(2) say that m = 1.5n, so
Because we know that m and n must b integers we can say that the very minimum m and n could be is,
m=3, n=2, 3=1.5*2
The astute observer would also note at this point that any other combination of m and n will be multiple of m and n. We can say that the ratio is
3m:2n
More importantly we can see,
[spoiler]3m*2n=6mn[/spoiler]
Thus any combination of m and n is going to result in a multiple of six (because we're multiplying any combination by 6. Thus (2) is sufficient.
The answer is B.
Could you please confirm that B is the OA?
Hope this helps.
Thanks,
Jared
-
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6 is a factor of product m*n -> m or n at least has 2
1. If m, n is odd -> no 2 factor -> not sufficient
2. m = 3/2 n -> 2m = 3n. n absolutely has 2 as its factor and m has 3 as its factor -> n=2k and m=3g -> m*n = 6*k*g, k,g in N.
-> B is the answer
1. If m, n is odd -> no 2 factor -> not sufficient
2. m = 3/2 n -> 2m = 3n. n absolutely has 2 as its factor and m has 3 as its factor -> n=2k and m=3g -> m*n = 6*k*g, k,g in N.
-> B is the answer