A dishonest milkman wants to make a profit on the selling of

Question

A dishonest milkman wants to make a profit on the selling of milk. He would like to mix water (costing nothing) with milk costing Rs.33 per litre so as to make a profit of 20% on cost when he sells the resulting milk and water mixture for Rs.36 In what ratio should he mix the water and milk?

(A) 1:20
(B) 1:10
(C) 1:8
(D) 1:4
(E) 6:11

(A) 1:20
(B) 1:10
(C) 1:8
(D) 1:4
(E) 6:11

bhatiamanu05 · Accepted Answer

Hi, This is a Mixture question.
For Solution Please see attachement.

Thanks AB,

pqhai · Answer

Name:
water = w (liter)
Milk = m (liter)

==> Cost = Price x Quantity = 0.33m
==> Revenue = Price x Quantity = 0.36(m + w)
==> Profit =  0.36(m+w) - 0.33m = 0.2*(0.33m)   
==> 0.36m + 0.36w - 0.33m = 0.066m
==> 0.036m = 0.36w
==> m/w = 0.36/0.036 = 10 
--OR--
 w/m = 1/10

B is correct.

Hope it helps.

sdpp143 · Answer

But you made a small mistake :wink:

C.P of 1 litre of mixture =(100/120)*36 =30

m3equals333 · Answer

my approach:

cost needed to net a 20% profit: 
(36-x)/x = .2
x=30

actual cost: 
33

solution (x=liters of water needed to be added to the 1liter of milk):
33/(1+x)=30
x = 1/10

so to get the cost down to 30 
Milk:Water
1:1/10

or (10/10):(1/10)

chandrae · Answer

Well. This might be one of the easiest methods. Solved this within a minute. In these type of questions plugging in the options might help you save a lot of time. For that, first choose the median ratio and plug in. You ll know whether the median ratio is right or wrong. If wrong, then you ll know whether the ratio is higher or lower than the median. So you ll eliminate 3 answer choices here. Out of the remaining two, plug in one ratio. If its right you got your answer. If its not, then the other one is your answer.

ScottTargetTestPrep · Answer

Solution:

Let the amount of water = 1 liter and the amount of milk = x liters in the mixture. We can create the equation:

33x * 1.2 = 36(x + 1)

39.6x = 36x + 36

3.6x = 36

x = 10

We see that the ratio of water to mike in the mixture is 1 to 10.

Answer: B

satya2029 · Answer

36(M+W)=1.2*33*M
36W=3.6M
W/M=1/10
B:)

saubhikbhaumik · Answer

Hi SCOTT,

Let the person buys 5 lit of milk. C.P = 5 x 33
Profit required = 1/5 * 5 * 33 = Rs. 33

Now as he is selling the mix for Rs. 36/lit, he is having a profit of 3 per lit. 
To get a profit of Rs. 33 he has to sell 33/3 lit of mix. = 11 lit of mix.

Therefore he mixes 6 lit of water to 5 lit of milk to make it 11 lit of mixture to reach his target profit of 20% i.e, Rs. 33.

So with 1 lit of Milk, he mixes 6/5 lit of water.

Where am I going wrong in this approach?

repellatquas · Answer

Alternatively:

We are given SP of mixture = 36
Profit % = 20
SP = CP* (1+P%)
36= CP (1.2)
CP= 30 (CP of mixture)

However, we are given that 1 Litre of milk costs Rs.33. 
If Rs 33 -> 1 Litre
Rs 30 -> 30/33 Litres = 10/11 Litres
Milk:Total = 10/11, Water: Total = 1/11
Therefore, Water to Mllk will be 1:10

nihilveritatis · Answer

tried algebra first which caused unnecessary confusion. Took a step back, realized that his cost is 30rs. That means he can only buy that much milk ---> 30/33 worth of milk = 10/11. Rest will be water. (1:10 final ratio)

A dishonest milkman wants to make a profit on the selling of

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