Value of n divided by 10?

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Value of n divided by 10?

by narisipalli » Sat May 08, 2010 10:09 am
What is the remainder when integer n is divided by 10?
1) When n is divided by 110 the remainder is 75.
2) When n is divided by 100 the remainder is 25.

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by akdayal » Sat May 08, 2010 11:09 am
I did not get your Question

But I think in both case it is 5.

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by iamseer » Sat May 08, 2010 11:50 am
narisipalli wrote:What is the remainder when integer n is divided by 10?
1) When n is divided by 110 the remainder is 75.
2) When n is divided by 100 the remainder is 25.
From 2:
n/100 gives remainder of 25. So, n=100m+25, where m is an integer.
(100m+25)/10 will give remainder of 5
Sufficient.

from 1:
n/110 gives remainder of 75. So, n=110q+75, where q is an integer.
(110q+75)/10 will give remainder of 5
Sufficient

IMO answer D
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by gmatmachoman » Sat May 08, 2010 11:51 am
akdayal wrote:I did not get your Question

But I think in both case it is 5.
st 1 :

n = 110K +75

n can take any value.

st 2

n=100Q + 25

combining st 1 & st 2

100Q -110K =50

when Q=6,K=5 ;100Q -110K =50

finding n, 100Q+25 =625

Remainder when N divided by 10 is 5

Y cant D???
take n =325, when divided by 100 :R is 5
when divided by 110 : R is 105
take n = 425 ,when when divided by 100 :R is 5
when divided by 110 : R is 95
Inconsistent .

SO I picked C

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by scoobydooby » Sat May 08, 2010 11:58 am
gmatmachoman wrote:
st 1 :

n = 110K +75

n can take any value.

st 2

n=100Q + 25

combining st 1 & st 2

100Q -110K =50

when Q=6,K=5 ;100Q -110K =50

finding n, 100Q+25 =625

Remainder when N divided by 10 is 5

Y cant D???
take n =325, when divided by 100 :R is 5
when divided by 110 : R is 105
take n = 425 ,when when divided by 100 :R is 5
when divided by 110 : R is 95
Inconsistent .

SO I picked C
st 1) n cant take any value- n can be 185, 295, 405.... which would leave a remainder of 5 when divided by 10

st 2) n can be 125, 225, 325, 425......which would leave a remainder of 5 when divided by 10

hence, D

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by harshavardhanc » Sat May 08, 2010 11:58 am
narisipalli wrote:What is the remainder when integer n is divided by 10?
1) When n is divided by 110 the remainder is 75.
2) When n is divided by 100 the remainder is 25.
The question is basically asking us to find the units digit of n.

Now, when a number n is divided by D, giving a quotient Q and a remainder R

n = DQ + R

in both the statements, DQ will be a multiple of ten, with units digit as 0. and then we are adding 5 to the units digit by adding either 75 or 25. therefore, in both the cases, the units digit will be 5.

Hence, each statement individually is sufficient to answer the question.
Last edited by harshavardhanc on Sat May 08, 2010 12:17 pm, edited 1 time in total.
Regards,
Harsha

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by gmatmachoman » Sat May 08, 2010 12:09 pm
harshavardhanc wrote:
narisipalli wrote:What is the remainder when integer n is divided by 10?
1) When n is divided by 110 the remainder is 75.
2) When n is divided by 100 the remainder is 25.
The question is basically asking us to find the units digit of n.

Now, when a number n is divided by D, giving a quotient Q and a remainder R

n = DQ + R

in both the statements, DQ will be a multiple of ten, with units digit as 0. and then we are adding 5 to the units digit by either adding 75 or 25. therefore, in both the cases, the units digit will be 5.

Hence, each statement individually is sufficient to answer the question.

ehehehehhe..i cant be stupid more than this!! I am doing same mistake of taking the same set !!

@harsha, do u remember i did the same kinda mistake sometime & was arguing with u & fibo!!

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by narisipalli » Sat May 08, 2010 12:25 pm
harshavardhanc wrote:
The question is basically asking us to find the units digit of n.

Now, when a number n is divided by D, giving a quotient Q and a remainder R

n = DQ + R

in both the statements, DQ will be a multiple of ten, with units digit as 0. and then we are adding 5 to the units digit by adding either 75 or 25. therefore, in both the cases, the units digit will be 5.

Hence, each statement individually is sufficient to answer the question.
That was indeed a nice way of explaining. Thanks Harsha.

Correct Answer: D