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
Difficult Math Question #48 - Ratios
This topic has expert replies
-
- Senior | Next Rank: 100 Posts
- Posts: 87
- Joined: Fri Jun 09, 2006 2:47 am
- Thanked: 2 times
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
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
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
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
-
- Legendary Member
- Posts: 752
- Joined: Sun May 17, 2009 11:04 pm
- Location: Tokyo
- Thanked: 81 times
- GMAT Score:680
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
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!!
-
- GMAT Instructor
- Posts: 1578
- Joined: Thu May 28, 2009 8:02 am
- Thanked: 128 times
- Followed by:34 members
- GMAT Score:760
sorry for a simple question but could you explain the bolded part? How do you do that?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