assume that initially he has 100gallons of milk that costs 100 USD @ USD 1 per gallon
To earn 20 % profit, he must earn USD 120, by selling the same qty of milk
But the selling price of milk = the cost price of the milk.
qty of milk and water mixture sold = 120/1 = 120 gallons
of the 120 lgallons, 100gallons are milk so the remaining must be water added.
Thus the amount of water added = 20 gallons
ratio of milk :water = 100:20 = 5:1
profit/loss Help Required
This topic has expert replies
Source: Beat The GMAT — Problem Solving |
GMAT/MBA Expert
- Anurag@Gurome
- GMAT Instructor
- Posts: 3835
- Joined: Fri Apr 02, 2010 10:00 pm
- Location: Milpitas, CA
- Thanked: 1854 times
- Followed by:523 members
- GMAT Score:770
Solution:
Let the ratio of milk and water in every gallon be r : 1.
Let the milk vendor sell 'g' gallons of milk at price 'p'.
Now this 'g' gallons of milk has 'g*r/(r+1)' amount of milk.
So cost price of 'g*r/(r+1)' amount of milk is 'p*r/(r+1)'.
So, 'p*r/(r+1)' is the cost price of milk which he is selling at price 'p'.
Or profit % = {p - p*r/(r+1)}/{p*r/(r+1)}*100 = {1/r}*100 = 20.
Or 1/r = 1/5.
Or r = 5.
So, ratio of milk is to water is 5:1.
Let the ratio of milk and water in every gallon be r : 1.
Let the milk vendor sell 'g' gallons of milk at price 'p'.
Now this 'g' gallons of milk has 'g*r/(r+1)' amount of milk.
So cost price of 'g*r/(r+1)' amount of milk is 'p*r/(r+1)'.
So, 'p*r/(r+1)' is the cost price of milk which he is selling at price 'p'.
Or profit % = {p - p*r/(r+1)}/{p*r/(r+1)}*100 = {1/r}*100 = 20.
Or 1/r = 1/5.
Or r = 5.
So, ratio of milk is to water is 5:1.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)
Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)
Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/












