Difficult Math Question #48 - Ratios

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Difficult Math Question #48 - Ratios

by 800guy » Mon Nov 06, 2006 10:49 am
There are 2 kinds of staff members in a certain company, PART TIME AND FULL TIME. 25 percent of the total members are PART TIME members others are FULL TIME members. The work time of part time members is 3/5 of the full time members. Wage per hour is same. What is the ratio of total wage of part time members to total wage of all members.

A. 1/4
B. 1/5
C. 1/6
D. 1/7
E. 1/8

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by rajs.kumar » Tue Nov 07, 2006 1:51 am
Answer is 1/6

workers PT:FT = 1:3

time worked FT:PT = 1:3/5

wage per hour is w

3/5 * w/(3/5 * w + 3w) = 1/6

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OA

by 800guy » Wed Nov 08, 2006 3:53 pm
here's the OA:

What is the ratio of total wage of part time members to total wage of all members.

You have calculated ratio of Part time-to-Full time.

P x/4 3y/5 3xy/4*5
A 3x/4 Y + x/4 3y/5 18xy/20

Ratio= p/a= 3xy/18xy= 1/6

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by takegmat » Mon Jan 29, 2007 10:36 am
An easier explanation would be to use the Princeton Review's Plugin method.

As we are asked to get compute ratio, we assume the following values.
Workers Count = 100, so PT = 25 & FT = 75
Total Work Time = 15 hrs, so FT = 15, PT = 3/5 * 15 = 9
Pay per hour = $D

So total wage = 75 * 15 * D + 25 * 9 * D = 25*9*D(1+5) = 25*9*D*6
So the ratio of wage of PT to all workers = 25 * 9 * D / 25*9*D*6 = 1/6

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by ghacker » Wed Jun 10, 2009 12:45 pm
#P : #F = 1:3

Sal_ P : Sal_F = 3:5

Hence the Total salary : salary P = 1:6

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by tohellandback » Wed Jun 10, 2009 7:54 pm
C.1/6
when a question contains only ratios or percentage, better substitute values
total number=100
part time=25
full time=75
part time work hours 3
full time work hours=5
wage per hour=10
part time total wage=10*3*25=750
full time total wage=10*5*75=3750
750/(3750+750)=1/6
The powers of two are bloody impolite!!

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by Osirus@VeritasPrep » Thu Jun 11, 2009 12:02 pm
takegmat wrote:An easier explanation would be to use the Princeton Review's Plugin method.

As we are asked to get compute ratio, we assume the following values.
Workers Count = 100, so PT = 25 & FT = 75
Total Work Time = 15 hrs, so FT = 15, PT = 3/5 * 15 = 9
Pay per hour = $D

So total wage = 75 * 15 * D + 25 * 9 * D = 25*9*D(1+5) = 25*9*D*6
So the ratio of wage of PT to all workers = 25 * 9 * D / 25*9*D*6 = 1/6
sorry for a simple question but could you explain the bolded part? How do you do that?

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interesting

by JeffB » Thu Jun 11, 2009 4:14 pm
A lot of different approaches to the problem, I did the same thing as tohellandback