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

Redeem

GMATPrep Test 1 : PS #14

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 8
Joined: Tue Oct 16, 2007 3:25 pm

GMATPrep Test 1 : PS #14

by kaizenwerks » Mon Nov 05, 2007 7:36 pm
Hi everyone,

I was wondering if there was a better/faster way to solve this problem?

I used back-solving to figure this one out.

74-58= 16

16 = 2 standard deviations => 8 = 1 standard deviation => 24 = 3 standard deviations

98 - 24 = 74

Any suggestions? Thanks.
Attachments
GMATprep_14.jpg
Best regards,

GMAT monkey
Top
Source: — Problem Solving |
Legendary Member
Posts: 645
Joined: Wed Sep 05, 2007 4:37 am
Location: India
Thanked: 34 times
Followed by:5 members

by camitava » Mon Nov 05, 2007 8:24 pm
Suppose, the st dev = x
Now according to the Qs,
58 + 2x = 98 - 3x
or, 5x = 40 => x = 8.

So the mean is = 58 + 2 * 8 = 74.
Correct me If I am wrong


Regards,

Amitava
Top
Newbie | Next Rank: 10 Posts
Posts: 4
Joined: Sat Jul 07, 2007 9:44 pm
Thanked: 1 times

by jerrygmat » Tue Nov 06, 2007 11:55 pm
I read the question as the following:

There is a gap of 5 standard deviations between 98 and 58.

98 - 58 = 40
40 / 5 = 8 each SD value

So either take 98 - 3(8) = 98 - 24 = 74 or 58 + 2(8)

Either way correct answer : )

HTH
Top
Post new topic Post Reply
• Page 1 of 1