2 DS questions

This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 71
Joined: Sun May 18, 2008 11:04 pm
Thanked: 1 times

2 DS questions

by charmaine » Wed Sep 10, 2008 7:17 pm
19. If x is an integer, what is the value of x?
(1) –2(x + 5) < -1
(2) – 3x > 9

ans. C

25. If x and y are consecutive odd integers, what is the sum of x and y?
(1) The product of x and y is negative.
(2) One of the integers is equal to –1.

ans. A

thanks u guys:)

Senior | Next Rank: 100 Posts
Posts: 54
Joined: Mon Oct 22, 2007 10:24 am
Thanked: 1 times

by oks » Wed Sep 10, 2008 8:49 pm
#19
x is an int
A. -2x - 10 < -1
-2x < -1+10
-2x <9
x> - 9/2 or -4.5

Not sufficient

B. -3x > 9
x<-3

Not sufficient

Together
-4.5<x<-3

Since x is an int, the only value in between that is an integer is -4

#25.
x and y are consecutive odd integers
A. xy is negative, so either x is negative or y is negative
since they are consecutive odd, x must be -1 and y must be 1 or vise versa

x+y = -1+1 = 0

Sufficient

B. if x = -1, then y could be either 1 or -3

Not sufficient