In what ratio must water be mixed with milk so as to make a

Question

In what ratio must water be mixed with milk so as to make a profit of 16*(2/3)% on selling the mixture at a rate same as that of cost price of milk.Given that milk man mixes bottled water instead of tap water and the cost of Bottled water is 20% of the cost of milk

A. 7:41
B. 1:6
C. 6:7
D. 5:23
E. 1:7

farful · Answer

Let x be the cost of milk.

First, you should recognize that 16.6666% = 1/6. If you don't, you can figure this out the long way...  16\frac{2}{3}% = \frac{48+2}{3}% = \frac{50}{3}% = \frac{50}{300} = \frac{1}{6}

So need to sell at x/(1+1/6) = x/(7/6) = 6x/7

We want the following equation to hold true, where a:b is the ratio of water:milk

\frac{a(.2x)+bx}{a+b} = \frac{6x}{7}

Plug in various answer choices, and you'll find D to be the correct answer choice.

\frac{5(.2x)+23x}{5+23} = \frac{x+23x}{28} = \frac{24x}{28} = \frac{6x}{7}

JusTLucK04 · Answer

I am not good with variables & so I assumed numbers

SP/CP= 7/6 ... to get a profit of 16.66

C.Price of Milk: 10
C.Price of water: 20% of 10=2

Assume that he mixes X ltrs of water per litre of Milk...
So when he actually goes to sell the adulterated milk in the market at the CP ie 10 the equation:
SP/CP= 10/[10(1-x)+2*x]
=10/(10-8x)

which should be equal to 7/6 if he intends to earn a 16.66% profit:10/(10-8x) =7/6
=> 24x= 5-4x
=> x= 5/28... :shock:

Where did I go wrong on this.. :help2

JusTLucK04 · Answer

Any Experts......??

In what ratio must water be mixed with milk so as to make a

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