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

Redeem

ps questions from gmatprep

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
Junior | Next Rank: 30 Posts
Posts: 11
Joined: Tue Oct 09, 2007 6:48 pm

Q17

by oct07 » Sun Dec 02, 2007 12:59 pm
Q17

Case 1:
t1 = 5/30=1/6
t2 = (x-5) / 60
t = t1+t2 = 1/6 + (x-5)/60 = (x+5)/60

Case 2:
t = x/60

Paraphrase the Qs:
[ (t1+t2) - t ] / t *100% =[ (x+5)/60 - x/60 ] / x/60 * 100%
= 5/x * 100% = 500%/x

As E

Please correct if I am wrong.
Top
Senior | Next Rank: 100 Posts
Posts: 42
Joined: Tue Nov 06, 2007 10:39 am

by lawalx » Sun Dec 02, 2007 2:51 pm
q34

pr A + Pr B + Pr C

Pr A = .30

Pr B = Pr. Not A * Pr B
= .70 * .30 = .21

Pr C = Pr Not A* Pr Not B * Pr C
= .70 * .70 * .30 = .147

add em up = .657
Top
Master | Next Rank: 500 Posts
Posts: 106
Joined: Tue Oct 09, 2007 12:25 pm
Thanked: 1 times

by xcise_science » Sun Dec 02, 2007 3:52 pm
hi thanks, but i don't understand.

i don't even understand what the p()=.30 represents.

pr A + Pr B + Pr C
Pr A = .30
Pr B = Pr. Not A * Pr B <== this is not clear either, why did you multiply by p(b)?
= .70 * .30 = .21
Pr C = Pr Not A* Pr Not B * Pr C
= .70 * .70 * .30 = .147
add em up = .657
Top
Master | Next Rank: 500 Posts
Posts: 106
Joined: Tue Oct 09, 2007 12:25 pm
Thanked: 1 times

by xcise_science » Sun Dec 02, 2007 4:01 pm
Q17,
hello,

how did you get (x+5)/60 here?
t = t1+t2 = 1/6 + (x-5)/60 = (x+5)/60

also, can you explain your calculations for how you 5/x here:
[ (t1+t2) - t ] / t *100% =[ (x+5)/60 - x/60 ] / x/60 * 100%
= 5/x * 100% = 500%/x


And was this a percent increase question? would it have been worthwhile to plug in numbers instead of working with x?

thanks!
Top
Post new topic Post Reply
• Page 1 of 1