BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Number properties

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 57
Joined: Sat Jan 24, 2009 7:45 am
Thanked: 1 times

Number properties

by ellexay » Tue Feb 10, 2009 5:22 pm
51. How many integers from 0 to 50, inclusive, have a remainder of 1 when divided by 3?

A.14 B.15. C.16 D.17 E.18

Soln: if we arrange this in AP, we get
4+7+10+.......+49

so 4+(n-1)3=49: n=16
C is my pick

I don't know what the OA is, but can someone tell me if C is indeed correct?

Thank you.
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 158
Joined: Tue Sep 30, 2008 8:47 am
Thanked: 23 times
Followed by:1 members
GMAT Score:660

by DeepakR » Tue Feb 10, 2009 5:32 pm
I think you have to include the number 1 as well.
1,4,7..49 hence a=1 and tn=49 so 49=1+(n-1)3. Therefore n=17 Ans.) D

- Deepak
Top
Senior | Next Rank: 100 Posts
Posts: 57
Joined: Sat Jan 24, 2009 7:45 am
Thanked: 1 times

by ellexay » Tue Feb 10, 2009 5:37 pm
Deepak,

I thought the question wanted integers that, when divided by 3, leave R1. That way, 1 wouldn't be included in the answer set.
Top
Senior | Next Rank: 100 Posts
Posts: 80
Joined: Mon Feb 02, 2009 6:36 am
Thanked: 10 times

by billzhao » Tue Feb 10, 2009 7:32 pm
I think that 1 should be included in the set because:
1. 1 is an integer
2. 1 is in the range from 0 to 50
3. 1 gives an remainder of 1 when dividing 3.
Yiliang
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 319
Joined: Wed Feb 04, 2009 10:32 am
Location: Delhi
Thanked: 84 times
Followed by:9 members

by sureshbala » Tue Feb 10, 2009 9:26 pm
billzhao wrote:I think that 1 should be included in the set because:
1. 1 is an integer
2. 1 is in the range from 0 to 50
3. 1 gives an remainder of 1 when dividing 3.
Perfect....1 must be included.
Top
Master | Next Rank: 500 Posts
Posts: 258
Joined: Thu Aug 07, 2008 5:32 am
Thanked: 16 times

by x2suresh » Tue Feb 10, 2009 9:32 pm
agree with D

1 should be included.
Top
Legendary Member
Posts: 1159
Joined: Wed Apr 16, 2008 10:35 pm
Thanked: 56 times

by raunekk » Tue Feb 10, 2009 9:44 pm
wats d OA??
Top
Legendary Member
Posts: 621
Joined: Wed Apr 09, 2008 7:13 pm
Thanked: 33 times
Followed by:4 members

by vittalgmat » Wed Feb 11, 2009 12:57 am
Here is an easy way.

50/3 = 16 integers.
However, this does not include 1, coz 1 divided by 3 has remainder =1.
So add 1.
==> 17 ie D
Top
Senior | Next Rank: 100 Posts
Posts: 57
Joined: Sat Jan 24, 2009 7:45 am
Thanked: 1 times

by ellexay » Wed Feb 11, 2009 6:19 am
Thanks to all! I understand now.

Unfortunately, the source from which I got this problem didn't have the OA for this one =(
Top
Post new topic Post Reply
• Page 1 of 1