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

Redeem

factors

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 1309
Joined: Wed Mar 17, 2010 11:41 pm
Thanked: 33 times
Followed by:5 members

by pradeepkaushal9518 » Mon Sep 13, 2010 1:58 am
positive factors of 42 are 2,3,6,7,14

factors of 56 are 2,4,7,8,14,28

so 3,6 are not factor of 56 so

answer is 2 B
A SMALL TOWN GUY
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 307
Joined: Sun Jul 11, 2010 7:52 pm
Thanked: 36 times
Followed by:1 members
GMAT Score:640

by limestone » Mon Sep 13, 2010 2:03 am
42 = 2*3*7
56=2*2*2*7
42 & 56 have the same " 2*7 "
total no. of factors of 42: 1;2;3;7; 2*3, 2*7, 3*7, 2*3*7 : 8 factors.
overlap factors that 56 can have with 42 is the factors of 2*7: 1;2;7;2*7 --- 4 factors.
So the no. of positive factors of 42 are not factors of 56 is: 8-4 = 4.
They're 3, 6 ( or 2*3), 42 (or 2*3*7), 21 ( or 3*7)
D is the answer.
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 146
Joined: Fri Jun 25, 2010 3:42 am
Thanked: 3 times
Followed by:1 members
GMAT Score:560

by alivapriyada » Mon Sep 13, 2010 2:20 am
OA is D

many thanx!!!!
Top
Post new topic Post Reply
• Page 1 of 1