Question

72 ml sampoo 57 rs one liter shampoo which price

Answer 1

$\textbf{Question}$ :

If 72 ml of a certain shampoo costs a person Rs. 57, then how much will the person paid for 1 l of that shampoo.

$\textbf{Answer}$:

Let the process of 1 litre of shampoo be Rs. x.

This problem can be solved by two methods:

1. Ratio and Proportion

2. Unitary Method

I will solve this question with both the methods for you.

$\textbf{Ratio and Proportion}$

In this method, you just need to write the values in the correct order. In this case, the order goes like this.

Capacity of shampoo : Cost of this capacity :: Wanted capacity of Shampoo : Wanted cost

So, 72ml : Rs. 57 :: 1000ml : Rs. x

Now, to find the value of x, you just need to multiply the extremes (Values at the ends) and means (Values in the middle).

i.e. 72x = 57000

x = 57000/72

x = 791.67

Thus, the cost is roughly Rs. 792.
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$\textbf{Unitary Method}$

Cost of 72 ml of shampoo = Rs. 57

Cost of 1 ml of shampoo = Rs. (57/72) = Rs. 0.791666.. or Rs. 0.792

Cost of 1000 ml of shampoo = Rs. (0.792 × 1000) = Rs. 792
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So, we get equal values in both the methods. Personally, I find the method of Ratio and Proportion easy and short but you can use the method most suitable for you.

Answer 2

First, As we know that :

$1 \: litre = 1000 \: ml$

Given that :

$Price \: of \: 72 \: ml \: shampoo = Rs. \: 57$

Now,

$Price \: of \: 72 \: ml \: shampoo \: = Rs. \: 57 \\ \\ = > Price \: of \: 1 \: ml \: shampoo = Rs. \: \frac{57}{72} \\ \\ Then, \: price \: of \: 1000 \: ml \: shampoo = \frac{57}{72} \times 1000 \\ \\ = > Price \: of \: 1000 \: ml \: ( 1 \: litre) shampoo \: = \: Rs. \: 791.66$ or Rs. 792 (approx)

So, the price of 1 litre shampoo will be Rs. 791.66