Answer:
6 liters
Step-by-step explanation:
Let x represent the amount of pure concentrate used to make the punch. Then the total amount of concentrate in the punch is ...
0.20·10 +1.00x = 0.50(10+x)
x +2 = 0.5x +5 . . . . . eliminate parentheses
0.5x = 3 . . . . . . . . . . .subtract 2+0.5x
x = 6 . . . . . . . . . . . . . multiply by 2
6 liters of pure concentrate must be added to make a 50% punch.
-6x - 3
Step-by-step-explanation:
I can help you with #20. For example, lets say 3/5, this fraction would be made up of 5 parts and 3 are covered, which doesn't make it full, if it was 5/5 it would be full. When you do something with a reciprocal you turn it over, so 3/5 would be turned over to 5/3, thus making it a whole number