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n00bpron00bpron00b
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Manhattan 5lbs : Algebra : Problem : 52

by n00bpron00bpron00b Wed Dec 03, 2014 8:40 pm

Hi Tommy,

Q) For the integers a,b,c, the sum of a and b is 75% of c

Col A : (3/4) (a+b)
Col B : (4/3) (c)

Is percentage of 0 or a negative value a valid condition to test ?
Do we not consider percentages only of non negative values ?

Thanks.
tommywallach
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Re: Manhattan 5lbs : Algebra : Problem : 52

by tommywallach Sat Dec 06, 2014 4:28 pm

For the integers a,b,c, the sum of a and b is 75% of c

Col A : (3/4) (a+b)
Col B : (4/3) (c)

a + b = .75c

You know, you could do the algebra here to create the columns (i.e. multiply both sides by 3/4, to create Column A), but yeah, I think I'd just think about it logically.

A = 1
B = -1
C = 0

A = 0
B= 0
C = 0

And (D) is proven. There are no constraints other than the ones given in the common information (all variables must be integers), so we're safe with negatives and 0.

-t
n00bpron00bpron00b
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Re: Manhattan 5lbs : Algebra : Problem : 52

by n00bpron00bpron00b Sat Dec 06, 2014 6:39 pm

Got it ! Thanks
tommywallach
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Re: Manhattan 5lbs : Algebra : Problem : 52

by tommywallach Tue Dec 16, 2014 6:03 pm

No problem!