-
dddanny2006
- Master | Next Rank: 500 Posts
- Posts: 209
- Joined: Thu Jan 12, 2012 12:59 pm
If d is a positive integer,is sqrt of d an integer?
1.Sqrt of 9d is an integer
2.Sqrt of 10d is NOT an integer.
Now this is how I understand it for Statement 1.
Let the integer be 2,that implies 9d=4 that implies d=4/9 Sqrt of 4/9 is not an integer--------NO
Let the integer be 9,that implies 9d=81,that implies d=9 Sqrt of 9 is 3 which is a integer------YES
Therefore it is insufficient.
Same is the case with Statement 2 as well and hence I think the answer should be E
The book says the answer is A.
Why is my approach incorrect??
Please clarify,
Dan
1.Sqrt of 9d is an integer
2.Sqrt of 10d is NOT an integer.
Now this is how I understand it for Statement 1.
Let the integer be 2,that implies 9d=4 that implies d=4/9 Sqrt of 4/9 is not an integer--------NO
Let the integer be 9,that implies 9d=81,that implies d=9 Sqrt of 9 is 3 which is a integer------YES
Therefore it is insufficient.
Same is the case with Statement 2 as well and hence I think the answer should be E
The book says the answer is A.
Why is my approach incorrect??
Please clarify,
Dan
