Good DS question

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Good DS question

by ankitbagla » Sat Jan 18, 2014 6:26 am
All the terms in Set S are integers. Five terms in S are even, and four terms are multiples of 3.
How many terms in S are even numbers that are not divisible by 3?
(1) The product of all the even terms in Set Sis a multiple of 9.
(2) The integers in S are consecutive.

OA to be announced later

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by Uva@90 » Sat Jan 18, 2014 6:54 am
ankitbagla wrote:All the terms in Set S are integers. Five terms in S are even, and four terms are multiples of 3.
How many terms in S are even numbers that are not divisible by 3?
(1) The product of all the even terms in Set Sis a multiple of 9.
(2) The integers in S are consecutive.

OA to be announced later
Hi Ankitbagla,
is OA B

Regards,
Uva.
Known is a drop Unknown is an Ocean

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by ankitbagla » Sat Jan 18, 2014 7:57 am
YES .. But your approach ?

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by Uva@90 » Sat Jan 18, 2014 8:35 am
ankitbagla wrote:YES .. But your approach ?
Here is how I did,

Given: 1) All terms in set S are integers
2) Five terms in S are even and 4 terms in S are multiples of 3

To Find: How many terms in set are even number and not divisible by 3?

lets take statement 2 first,
statement 2: The integers in S are consecutive.
let Set S consist of
3,4,5,6,7,8,9,10,11,12
So number of even number and not divisible by 3 is 3{4,8,10}

similarly if you take set you will end up with only 3 numbers.
hence sufficient.

Statement 1: The product of all the even terms in Set Sis a multiple of 9.
Let Set S = {6,6,6,6,2}
here number of even number and not divisible by 3 is 1

consider another set S = {6,6,2,2,2,3,3}
here number of even number and not divisible by 3 is 3
hence insufficient.

Answer is B

Regards,
Uva.
Known is a drop Unknown is an Ocean