[url=https://www.postimage.org/image.php?v=aVvIpCi][img]https://www.postimage.org/aVvIpCi.jpg[/img][/url]
[url=https://www.postimage.org/image.php?v=aVvIC50][img]https://www.postimage.org/aVvIC50.jpg[/img][/url]
[url=https://www.postimage.org/image.php?v=Pq1KOxzi][img]https://www.postimage.org/Pq1KOxzi.jpg[/img][/url]
For the first one I feel d can maximum take a value 6. So the info would not help.
2. whether r is -ve or +ve as long as p=r one can conclude. Why is the second condition needed?
[/img]
GMATPrep
This topic has expert replies
-
- Legendary Member
- Posts: 645
- Joined: Wed Sep 05, 2007 4:37 am
- Location: India
- Thanked: 34 times
- Followed by:5 members
madhavi, ur first Qs -
500 is the multiple of 100 closet to x -> Can be x = 451 or 499
400 is the multiple of 100 closet to y -> Can be y = 351 or 399
So x + y = 451 + 399 = 850 = Closet to 900
or = 451 + 351 = 802 = closet to 800
So E is the best option to chose.
Ur second qs -
To me, its coming as A which I think u have also chosen. Don't getting why C is the OA(If it is ...)?
Ur third qs -
f = 30! - right?
Now by stmt - 1 10^d is a factor of f. But d can be 1, 2, 3 or so.
But in stmt - 2, it is saying that d > 6.
Here we can get the value of d and that is 7.
Now question is - how? Look, 30! = product of first 30 integers
For 10, 20 and 30 there will be 3 zeroes coming at the end. Now for every 5 at the unit digit, the product will be zeroes at the unit or ten digit. It will be like - 25 x 4, 15 x 2 and 6 x 5. In (25 x 4), we are getting 2 zeroes for the rest, only 1 zero at the end. So number of zeros that can come in 30! is (3 [For 10,20 and 30] + 2 [25 * 4] + 1 [15 * 2] + 1 [6 * 5] ) = 7.
So d = 7. Am i clear to explain?
500 is the multiple of 100 closet to x -> Can be x = 451 or 499
400 is the multiple of 100 closet to y -> Can be y = 351 or 399
So x + y = 451 + 399 = 850 = Closet to 900
or = 451 + 351 = 802 = closet to 800
So E is the best option to chose.
Ur second qs -
To me, its coming as A which I think u have also chosen. Don't getting why C is the OA(If it is ...)?
Ur third qs -
f = 30! - right?
Now by stmt - 1 10^d is a factor of f. But d can be 1, 2, 3 or so.
But in stmt - 2, it is saying that d > 6.
Here we can get the value of d and that is 7.
Now question is - how? Look, 30! = product of first 30 integers
For 10, 20 and 30 there will be 3 zeroes coming at the end. Now for every 5 at the unit digit, the product will be zeroes at the unit or ten digit. It will be like - 25 x 4, 15 x 2 and 6 x 5. In (25 x 4), we are getting 2 zeroes for the rest, only 1 zero at the end. So number of zeros that can come in 30! is (3 [For 10,20 and 30] + 2 [25 * 4] + 1 [15 * 2] + 1 [6 * 5] ) = 7.
So d = 7. Am i clear to explain?
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
-
- Master | Next Rank: 500 Posts
- Posts: 214
- Joined: Wed Nov 14, 2007 6:30 am
- Thanked: 15 times
Nice explantions camitava
Lets chk the one lft out ...
From 1 p = r
Let say p = 2 ---- case 1
1/2 > 2/6 ..Yes
Let say p = -2 ---- case 2
-1/2 > -1/3 No
hence Insufficient
From 2 r > 0 so case 2 above is eliminated ..and also p =r so only case 1 holds
hence C
Hope this helps
Lets chk the one lft out ...
From 1 p = r
Let say p = 2 ---- case 1
1/2 > 2/6 ..Yes
Let say p = -2 ---- case 2
-1/2 > -1/3 No
hence Insufficient
From 2 r > 0 so case 2 above is eliminated ..and also p =r so only case 1 holds
hence C
Hope this helps
-
- Legendary Member
- Posts: 645
- Joined: Wed Sep 05, 2007 4:37 am
- Location: India
- Thanked: 34 times
- Followed by:5 members
Thanks sujaysolanki! Again a miss from my side... I misunderstood the problem at all. God where are you? Pls help meeeeeeeeeeeee ...
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava