Answer:
15 mL of the solution with 20% water will be needed.
Step-by-step explanation:
Use the inverse relationship
10 mL * (18-15)% = x mL * (20-18)%
x = 10 mL * (3/2) = 15 mL
4 5/8 = 37/8
2 7/8= 23/8
37/8-23/8=14/8=1 6/8=1 3/4
Answer:
C
The "inverse operation" is just a way of saying "what do you do to isolate the variable". In this case, we isolate y, so we have to move all terms to the right side. To do that, we subtract 12 from each side to there will only be "y" on the left side.
First find how many units of solution there is:
500* 2% = 500(.02) = 10 units
You need 10 units of solution in 'x' units of a 10% solution.
x*10% = 0.1x = 10 units -----> x = 10/0.1 = 100
100 units are needed
