Question

2)Out of 20 litres, a milkman sells some milk at the rate of 15 rupees per litre and remaining at 20 rupees per litre. If he gets rupees 340 on selling it, how much milk he sold at each rate.​

Answer 1

Answer:

12 and 8 : HOPE IT EXPLAINS IT

Step-by-step explanation:

Let their is two type of milk x and y

So, ATQ  total milk is 20 litres.

So,

x + y = 20

x = 20 - y -------------equation (1)

Now,

Milkman sold milk at 15 rs per litre = 15 X x

                         = 15x

Milk sold at 20 rs per litre = 20 X y

          = 20y

total money = 340 rs

SO, ATQ

15x + 20y = 340  ------------equation (2)

putting value of x from equation (1) in equation (2)

15(20-y) + 20y = 340

300 - 15y + 20y = 340

300 + 5y = 340

5y = 340 -300

5y = 40

y = 40/5

y = 8

Putting value of y in equation (1)

x = 20 - 8

x = 12

So, milkman sold 12 litres milk at rate of 15 and 8 litres of milk at rate of 20 rs.