Question

4 l are drawn from a container full of milk and is then filled with water. this operation is perfprmed three more times. the ratio of the quantity of milk left

Answer 1

Suppose a container contains  

x

units of a liquid from which  

y

units are taken out and replaced by water. After  

n

operations, quantity of pure liquid  

=

x

(

1

−

y

x

)

n

units.

milk contained by the container now  

=

40

(

1

−

4

40

)

3

=

40

(

1

−

1

10

)

3

=

40

×

9

10

×

9

10

×

9

10

=

4

×

9

×

9

×

9

100

=

29.16