If M and Nare integers, is {10^M + N}/3 an integer?
1. N = 5
2. MN is even
* Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient
* Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient
* BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient
* EACH statement ALONE is sufficient
* Statements (1) and (2) TOGETHER are NOT sufficient
How to solve this ?
properties of numbers
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- Lattefah84
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- ajith
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A number is divisible by 3 if sum of digits is divisible by 3Lattefah84 wrote:If M and Nare integers, is {10^M + N}/3 an integer?
1. N = 5
2. MN is even
* Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient
* Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient
* BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient
* EACH statement ALONE is sufficient
* Statements (1) and (2) TOGETHER are NOT sufficient
How to solve this ?
The sum of digits for 10^M+N = N+1 (if M>0 and N>0)
1. Not sufficient ( had the question been that M, N are positive integers then this would have been sufficient)
2. Not Sufficient (M or N can be negative)
1&2 combined also is not good enough
IMO E
(A if M,N are strictly positive)
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i didn't know where to start with this one
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Ajith,ajith wrote:
A number is divisible by 3 if sum of digits is divisible by 3
The sum of digits for 10^M+N = N+1 (if M>0 and N>0)
1. Not sufficient ( had the question been that M, N are positive integers then this would have been sufficient)
2. Not Sufficient (M or N can be negative)
1&2 combined also is not good enough
IMO E
(A if M,N are strictly positive)
How do you calculate sum of digits in a decimal?
You say that statement 1 is insufficient. Whether M is -ve or +ve, you always have the sum of digits as 1 in 10^M. Am i wrong?
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You can only use the "sum of digits" rule to check for divisibilty by 3 if the value is an integer. Not a decimal e.g. 2.01 is not divisible by 3 even though the sum of its digits =3.papgust wrote:Ajith,ajith wrote:
A number is divisible by 3 if sum of digits is divisible by 3
The sum of digits for 10^M+N = N+1 (if M>0 and N>0)
1. Not sufficient ( had the question been that M, N are positive integers then this would have been sufficient)
2. Not Sufficient (M or N can be negative)
1&2 combined also is not good enough
IMO E
(A if M,N are strictly positive)
How do you calculate sum of digits in a decimal?
You say that statement 1 is insufficient. Whether M is -ve or +ve, you always have the sum of digits as 1 in 10^M. Am i wrong?
So, since M can be negative, it is insufficient.
- Lattefah84
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And how can I know if the 10^M is equal to N+1? Shouldn't it be 10^M= - 5ajith wrote:A number is divisible by 3 if sum of digits is divisible by 3Lattefah84 wrote:If M and Nare integers, is {10^M + N}/3 an integer?
1. N = 5
2. MN is even
* Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient
* Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient
* BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient
* EACH statement ALONE is sufficient
* Statements (1) and (2) TOGETHER are NOT sufficient
How to solve this ?
The sum of digits for 10^M+N = N+1 (if M>0 and N>0)
1. Not sufficient ( had the question been that M, N are positive integers then this would have been sufficient)
2. Not Sufficient (M or N can be negative)
1&2 combined also is not good enough
IMO E
(A if M,N are strictly positive)