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M13 Q30 -> wrong solution given [#permalink]
 08 Feb 2010, 08:55
Question :
Is a*b*c divisible by 24 ?
1. a , b , and c are consecutive even integers
2. a*b is divisible by 12
Solution:
Statement (1) by itself is sufficient. One of any three consecutive even integers is divisible by 3. Because this integer is even, it is also divisible by 6. When multiplied by two more even integers, it renders a product that is divisible by 24.
Statement (2) by itself is insufficient. We need to know something about c .
As per me, 0 is an even number.
So, as per S1, if a, b and c are consecutive integers, it can be even 0,2,4. Then in that case, number won't be divisible by 24.
Hence, the answer should be 'c'.
Guys please confirm !!
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Re: M13 Q30 -> wrong solution given [#permalink]
08 Feb 2010, 09:25
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bhanupra wrote: Question :
Is a*b*c divisible by 24 ?
1. a , b , and c are consecutive even integers
2. a*b is divisible by 12
Solution:
Statement (1) by itself is sufficient. One of any three consecutive even integers is divisible by 3. Because this integer is even, it is also divisible by 6. When multiplied by two more even integers, it renders a product that is divisible by 24.
Statement (2) by itself is insufficient. We need to know something about c .
As per me, 0 is an even number.
So, as per S1, if a, b and c are consecutive integers, it can be even 0,2,4. Then in that case, number won't be divisible by 24.
Hence, the answer should be 'c'.
Guys please confirm !! 0*2*4 = 0 0/24 = 0 Answer results in an integer which means 0 is divisible by 24
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Re: M13 Q30 -> wrong solution given [#permalink]
08 Feb 2010, 11:00
true A is correct..I too made the same mistake. Manhattan Number properties book has a question similar to this.
_________________
FEB 15 2010 !!
well I would not disturb you after the D-day ..so please !!!
It Will Snow In Green , One Day !!!!
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Re: M13 Q30 -> wrong solution given [#permalink]
09 Feb 2010, 21:38
Thanks so much ..!!
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Re: M13 Q30 -> wrong solution given [#permalink]
11 Feb 2010, 10:08
10,12,14
a,b,c
a*b
10*12=120; 120/12=10
a*b*c=120*14=1680 ; 1680/24=70.
hence A
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Re: M13 Q30 -> wrong solution given [#permalink]
12 Feb 2010, 19:57
0 is divisible by all numbers!
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Re: M13 Q30 -> wrong solution given
[#permalink]
12 Feb 2010, 19:57
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