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DS: Remainder

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DS: Remainder

by stop@800 » Mon Oct 20, 2008 2:25 pm
What is the remainder when the positive integer x is divided by 8?

1. when x is divided by 12, the remainder is 5.
2. when x is divided by 18, the remainder is 7.

Please avoid the number substitution and solve this using algebric equations.

Thanks in advance.
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by cramya » Tue Oct 21, 2008 5:26 am
Whats the OA?

I am getting C. Since I am not doing it algebrically dint want to post the solution since you may have worked it out with numbers already.
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by bluementor » Tue Oct 21, 2008 6:02 am
IMO E, but I'm not sure of this answer.

Whats the OA and source of this question?

-BM-
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Re: DS: Remainder

by sudhir3127 » Tue Oct 21, 2008 6:05 am
stop@800 wrote:What is the remainder when the positive integer x is divided by 8?

1. when x is divided by 12, the remainder is 5.
2. when x is divided by 18, the remainder is 7.

Please avoid the number substitution and solve this using algebric equations.

Thanks in advance.
i go for E.

statement 1.

x = 12a+5.........................not sufficient

statement 2.

x = 18b+11, .........................not sufficent ..

combining 1 and 2.

we know that the first number which statisfies it is 29 and subsequent numbers will be of the form 36*m+29 where 36*m is a number that will be the multiple of the LCM of 12 and 18

thus the numebers will be 29, 65 (36*1+29), 101 (36*2+29), 137(36*3+29)

thus when the above numbers are divided by 8... the remainders can be either 5 or 1.

hence E.

hope that helps.. do let us know the OA.
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by bhabani » Tue Oct 21, 2008 8:04 am
why is it 18b+11 ??? it shuold be 18b+7 isn t ?
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by stop@800 » Wed Oct 22, 2008 9:28 am
bhabani wrote:why is it 18b+11 ??? it shuold be 18b+7 isn t ?
True

I was also thinking that how come 29 leave a remainder of 7.

with 7, we will not have any common term
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by cramya » Wed Oct 22, 2008 7:36 pm
Refer to
https://www.beatthegmat.com/ds-t7158.html

stop@800, Is your problem correct? In the post everyhting is the same except statement 2

Let me know
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by stop@800 » Wed Oct 22, 2008 10:59 pm
cramya wrote:Refer to
https://www.beatthegmat.com/ds-t7158.html

stop@800, Is your problem correct? In the post everyhting is the same except statement 2

Let me know
The problem is correct but source may not be the reliable one.
Also, the link you mentions has C as answer and answer for this one is E.
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by cramya » Thu Oct 23, 2008 8:51 pm
If you look at Gabriel's post the answer is E and not C
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by stop@800 » Thu Oct 23, 2008 9:56 pm
cramya wrote:If you look at Gabriel's post the answer is E and not C
Buddy, that question is different and this one is different.
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