# Download Mrunal [Aptitude] Alligations,Mixtures,Alloys: Water,Milk,Wine Mixing: Weighted Average Made Easy for CSAT,CAT,CMAT,IBPS Aptitude » Mrunal PDF

Title Mrunal [Aptitude] Alligations,Mixtures,Alloys: Water,Milk,Wine Mixing: Weighted Average Made Easy for CSAT,CAT,CMAT,IBPS Aptitude » Mrunal 390.2 KB 9
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(M minus 0) =2 lit…..(ii)
We cannot do (0 minus M) because M is concentration of wine in the final mixture. It
is bigger than 0% and smaller than 100%.

Matter is over. Sum is solved. Game Finished.
Just divide equation (i) from equation (ii) or you can do reverse divide (ii) from (i),
you’ll get the value of “m%” in either case. See this image for actual calculation

Final answer= the concentration of Wine in given mixture is 16.66%
Which also means, concentration of Water in this given mixture
=100 – 16.6% ;because conc. Of water + conc. Of wine =100%
=83.4% water.
Ofcourse real exam questions won’t be this easy so lets take a few cases.

Case: Average price and profit after mixing two solutions

16 lit. of Soda is mixed with 5 lit. of Wine. Price of this Soda is Rs.12 / lit
and price of wine Rs.33/lit. What is the average price of this mixture.

http://img26.imageshack.us/i/eq2s.png/
http://img831.imageshack.us/i/dividenrule.png/

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Sidenotes

Answer for average must be between the two extremes: 12 and 33.
So if you get the answer outside this [12-33] range, know that you’ve made
mistake somewhere in calculation.
Whenever possible, do this componendo method to solve the sum quickly
without making mistakes in lengthy multiplications. At time you’ll have to use
“Dividendo” principle i.e. same but instead of adding (+) bottom to top, you
subtract (-) bottom from top.

Back to the question:

Price of Final mixture is 17 Rs. Per litre. But this is the ‘cost-price’ for the
bartender. HE wants to make 25% profit on this.
What is 25% of 17? = 17 x (25/100) = Rs.4.25
So his Selling price = Cost price + profit of 25% =17 + 4.25 = 21.25

Quicker method for profit calculation

25% =25/100 = 1/4
You add this one fourth part to the total one part of given cost price.
So 1 plus ¼ =5/4 parts.
Multiply (5/4) with 17 and you get 21.25 = our selling price.
Final Answer : Bartender should sell this mixture at 21.25 rupees per liter, if he
wants to make 25% profit.
Same way, if he had asked to find selling price for 50% profit, multiply 17 with
3/2. (because 50%=1/2)

Case: Add water to decrease the concentration (dilution)

http://img694.imageshack.us/i/componedo.png/