Question

20 litres of a mixture contains milk and water in the ratio of 3:1.How much milk must be added to this mixture so as to have milk and water in the ratio 4:1?

Answer 1

Thus this is the easiest method I know...hope help u

Answer 2

Total amount of mixture=20l
Let the amount of water=x
:. Amount of milk=3x
Since the ratio is 3:1 (milk:water)
:. equation-Amount of milk+amount of water=total amount of mixture.
:. putting value
→3x+x=20
→4x=20
→x=20/4
→x=5
:. Total amount of milk=3x=3×5=15l
& Total amount of water=x=5l
Now according to question,
Let the new amount of water be y
Amount of milk=4y
Amount of water=y
:. Equation-Amount of milk+amount of water=total amount of mixture
:. putting value,
→4y+y=20
→5y=20
→y=20/5
→y=4
:. current total amount of milk=4y=4×4=16l
& Current total amount of water=y=4l
Now,
Let the required amount of milk be z.
:. Equation-
required amount of milk=current amount of milk-original amount of milk
:. putting value,
→z=16-15→
z=1l
:. Required amount of milk=1l
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