An after shave lotion contains 50% ethyl alcohol. How much water must be added to 6 fluid ounces of this lotion to reduce it to one which is 75% nonalcoholic?
2007-12-05 17:49:23 · 5 answers · asked by precious 3 in Science & Mathematics ➔ Mathematics
x = amount of water to be added
0.50(6) + x = 0.75(6+x)
3 + x = 4.5 + 0.75x
0.25x = 1.5
x = 6 oz of water
2007-12-05 17:54:11 · answer #1 · answered by Anonymous · 0⤊ 0⤋
answer is 6 oz water.
how?
50% of 6oz + xoz = 75% of (x + 6)oz
=> 3 + x = 3/4(x + 6)
=> 12 + 4x = 3x + 18
=> x = 6
2007-12-06 01:55:38 · answer #2 · answered by sv 7 · 0⤊ 0⤋
50% of 6 oz. is 3 oz. So to make the mixture 75% non-alcoholic, you need to add 9 oz. of water. Since already 3 oz. exists in the original mixture, you need to add another 6 oz. of water now.
2007-12-06 01:55:18 · answer #3 · answered by Swamy 7 · 0⤊ 0⤋
Let x =shave solution ,water content
x =0.5(6) =3
y = water added to make solution 75% non-alcoholic
.5(6) + y =(3 +y)(0.75), water solution(2)
3. +y = 22.5 +.75y
.25y =25.5
y = 25.5/0.25
y =102 fl.ounces
2007-12-06 02:54:44 · answer #4 · answered by Anonymous · 0⤊ 0⤋
0.5 * 6oz = 3oz
0.25 * x = 3oz
x = 12oz
So add 6oz of water.
2007-12-06 01:53:18 · answer #5 · answered by feanor 7 · 0⤊ 0⤋