Question

How much water should be reduce 9 ml lotion containing 50% alcohol to a lotion containing 30% alcohol?

Answer 1

Given :

• 9 ml lotion containing 50% alcohol
• a lotion containing 30% alcohol

To find :

• How much water should be reduce 9 ml

Solution :

alcohol in 9 ml lotion = 9 x (50/100) ml

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀ = 4.5 ml

Let x my of water is to be added to it

4.5/(9 + x) x 100 = 30

4.5/(9 + x) = 30/100

= 3/10

3(9 + x) = 4.5 x 10

3x = (45 - 27)

x = 18/3

x = 6

=> water to be added = 6ml