5 litres of water is added to a certain quantity of pure milk costing $3 per litre. If, by selling the mixture at the same price as before a profit of 20% is made, what is the amount of pure milk in the mixture?
My approach:
Quantity of milk = x lts
Cost of milk per lt = $3
Water added = 5 lt
Total quantity of mix = x+5 lts
Selling Price of milk = 3x
Mixture (x+5) lts is also sold at $3 per lt. Therefore SP of mixture = 3(x+5)
I am stuck after this. How do i set up the 20% profit?
Help needed.
Thank you
Mixture Question
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- smackmartine
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I think if you had posted the options, you would have gotten some reply. Anyways
Let the quantity of pure milk is x
so , total cost of x liter @ $3 per liter will be 3x
After adding 5 liters of water and selling @ same rate, New Total cost is 3(x+5)
As per question , profit is 20% => [3(x+5)-3x]/3x =1/5
15/3x = 1/5 => x = 25 . So, initial quantity of milk was 25 liters.
Now if you want to cross verify the answer :
Initial quantity of milk = 25 liters , Total cost = 3*25 = $ 75
After adding 5 liters of water and selling the solution @ same rate, the total cost will be 3*(25+5)= $90
Now, profit = [(90-75)/75 ]*100 = [15/75]*100 = [1/5]*100 = 20 (which is given)
Let the quantity of pure milk is x
so , total cost of x liter @ $3 per liter will be 3x
After adding 5 liters of water and selling @ same rate, New Total cost is 3(x+5)
As per question , profit is 20% => [3(x+5)-3x]/3x =1/5
15/3x = 1/5 => x = 25 . So, initial quantity of milk was 25 liters.
Now if you want to cross verify the answer :
Initial quantity of milk = 25 liters , Total cost = 3*25 = $ 75
After adding 5 liters of water and selling the solution @ same rate, the total cost will be 3*(25+5)= $90
Now, profit = [(90-75)/75 ]*100 = [15/75]*100 = [1/5]*100 = 20 (which is given)
nadib002 wrote:5 litres of water is added to a certain quantity of pure milk costing $3 per litre. If, by selling the mixture at the same price as before a profit of 20% is made, what is the amount of pure milk in the mixture?
My approach:
Quantity of milk = x lts
Cost of milk per lt = $3
Water added = 5 lt
Total quantity of mix = x+5 lts
Selling Price of milk = 3x
Mixture (x+5) lts is also sold at $3 per lt. Therefore SP of mixture = 3(x+5)
I am stuck after this. How do i set up the 20% profit?
Help needed.
Thank you
- GMATGuruNY
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The cost of the milk is irrelevant.nadib002 wrote:5 litres of water is added to a certain quantity of pure milk costing $3 per litre. If, by selling the mixture at the same price as before a profit of 20% is made, what is the amount of pure milk in the mixture?
My approach:
Quantity of milk = x lts
Cost of milk per lt = $3
Water added = 5 lt
Total quantity of mix = x+5 lts
Selling Price of milk = 3x
Mixture (x+5) lts is also sold at $3 per lt. Therefore SP of mixture = 3(x+5)
I am stuck after this. How do i set up the 20% profit?
Help needed.
Thank you
Let m = volume of the pure milk.
To make a 20% profit, the added water must increase the volume of the pure milk by 20%.
Thus, the 5 liters of added water must be 20% of the volume of the milk:
5 = .2m
m = 5/.2 = 25.
For many test-takers, the easiest approach would be the plug in the answers, which would represent the amount of milk:
Answer choice: 25 liters of milk
Cost at $3 per liter = 3*25 = $75.
Volume of mixture = milk + water = 25+5 = 30 liters.
Selling price = 3*30 = $90.
Profit = 90-75 = 15, which is 20% of the cost of the milk.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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