Question

In what ratio must a grocer mix two varieties of pulses costing Rs. 15 and Rs. 20 per kg respectively so as to get a mixture worth Rs. 16.50 kg?

Answer 1

Let the first variety of pulse be x kg & second variety of pulse be y kg

So total cost of(x+y) kg is Rs.( 15x+20y.)

So cost of 1 kg mixture is Rs. (15x+20y)/x+y.
according to question,

(15x+20y)/(x+y)=16.50

(15x+20y)/(x+y)=33/2

33x+33y=30x+40y

3x=7y

x:y=7:3

Answer 2

$\huge\boxed{Answer\:=\:7\::\:3}$

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$\huge\underline\mathfrak\red{Explanation}$

Let we suppose,

x kilogram of First is taken.

(1-x) kilogram of second is taken.

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Then, According to question,

The price of mixture will be :

15x + 20(1-x) = 20-5x......(i).

Also,

Price of mixture = 16.50 rs. ( Given )......(ii).

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From equation (i) and (ii),

20-5x = 16.5

-5x = 16.5-20

-5x = - 3.5

x = 3.5/5

x = 0.7

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Hence, The required ratio is :

x : 1-x

→ 0.7 : 1-0.7

→ 0.7 : 0.3

→ 7:3 ( required answer )

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