Successive Div

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Successive Div

by ygdrasil24 » Wed Jun 12, 2013 4:42 am
A certain number when successively divided by 8 and 11 leaves remainders of 3 and 7 respectively. What will be remainder when the number is divided by the product of 8 and 11, viz 88?

A. 3
B. 21
C. 59
D. 68
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by Brent@GMATPrepNow » Wed Jun 12, 2013 5:56 am
ygdrasil24 wrote:A certain number when successively divided by 8 and 11 leaves remainders of 3 and 7 respectively. What will be remainder when the number is divided by the product of 8 and 11, viz 88?

A. 3
B. 21
C. 59
D. 68
This question isn't up to GMAT standards.
What does it mean to successively divide by 8 and 11?

For example, if we begin with 51 and divide by 8 we get 6 with remainder 3.
Now what? Do we take the 6 and divide by 11, or do we somehow include the remainder?
After all, 51 divided by 8 does not equal 6. So, we really should include the remainder of 3 somewhere when we divide by 11.

Since it's unclear what we're supposed to do here, I think the question should be reworded to clearly express its message.

What's the source of this question?

Cheers,
Brent
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by ygdrasil24 » Wed Jun 12, 2013 10:04 am
Brent@GMATPrepNow wrote:
ygdrasil24 wrote:A certain number when successively divided by 8 and 11 leaves remainders of 3 and 7 respectively. What will be remainder when the number is divided by the product of 8 and 11, viz 88?

A. 3
B. 21
C. 59
D. 68
This question isn't up to GMAT standards.
What does it mean to successively divide by 8 and 11?

For example, if we begin with 51 and divide by 8 we get 6 with remainder 3.
Now what? Do we take the 6 and divide by 11, or do we somehow include the remainder?
After all, 51 divided by 8 does not equal 6. So, we really should include the remainder of 3 somewhere when we divide by 11.

Since it's unclear what we're supposed to do here, I think the question should be reworded to clearly express its message.

What's the source of this question?

Cheers,
Brent
Source is GmatClub, I too got confused there, some expert had replied to the problem assuming number of the form 51K ,

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by Brent@GMATPrepNow » Wed Jun 12, 2013 10:07 am
Yeah, the solution (with answer C as the correct response) essentially disregards the remainder in the first division.

I'd just skip the question if I were you.

Cheers,
Brent
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