Odd and Even

IMO C

Statement 1 will give us either 11 or 12 odd integers depending on the value of Y

Lets assume that x = 1 and y = 25 (even numbers between x and y = 12 (2,4,6,8,10,12,14,16,18,20,22,24
Odd numbers (3, 5.....,23) = 11 since y = 25
But if x= 1 and y = 26 then also we have 12 even nos between x and y but 12 odd numbers (3,5,...23, 25)

So we get odd nos = 11 or 12 depending on the value of y
So St 1 insuff

Statement 2 : there are 24 integers between x and y

if x = 1 then y = 26 then we have 12 even and 12 odd nos between them
if x= 2 then y = 27 then we have 12 even (4,6,8,10,12,14,16,18,20,22,24,26 ) and 12 odd (3,5,7,9,11,13,15,17,18,21,23,25)

So Statement 2 is sufficient

IMO (B)

Am I right?

ronniecoleman wrote:IMO C

Ronnie,

I will really appreciate, if we don't turn this forum into a IMO garbage. Nobody really learns or benefits from IMOs.

Thanks for understanding,

gmat009 wrote:how many odd integers are greater than integer X and less than the integer y?
1. there are 12 even integers greater than x and less than y
2. there are 24 integers greater than X and less than Y

Pls post the answer with spoiler....

Agree with srisl11

In fact you can remember this rule:

If there are even number of integers, then the number of even and odd integers is exactly equal.

1-10: There are 10 integers. 5 integers are odd & 5 are even.
1-12: There are 12 integers. 6 odd and 6 even.
1-24: 24 integers. 12 odd and 12 even.

However if there are odd number of integers, then either the # of odd integers is one less than the # of even or vice versa.

1-5: There are 5 integers. 3 odd & 2 even
2-6: There are 5 integers. 3 even & 5 odd.

for such questions, why do we have to assume that all integers will be consecutive integers? why can't there be a repetition of some odd integers?

the answer should be E. i don't understand how we've assumed that the integers between x and y are consecutive when this hasn't been mentioned in the question.

arpitrai wrote:for such questions, why do we have to assume that all integers will be consecutive integers? why can't there be a repetition of some odd integers?

the answer should be E. i don't understand how we've assumed that the integers between x and y are consecutive when this hasn't been mentioned in the question.

I was thinking E as well. If the question stem doesn't t specify that the integers are consecutive, we can't assume they are, right?

What's the answer?