Answer:
- 750 mL of 0.23% solution
- 250 mL of 0.03% solution
Step-by-step explanation:
Let x represent the quantity (in liters) of the higher percentage solution, the 0.23% solution. Then 1-x will be the quantity of 0.03% solution. The amount of salt in the mix is ...
0.23%·x +0.03%·(1 -x) = 0.18%·1
Multiply by 100% and subtract 3:
20x = 15
x = 15/20 = 0.75 . . . . liters of 0.23% solution
1-x = 1-0.75 = 0.25 . . liters of 0.03% solution
The lab tech needs 750 mL of 0.23% solution and 250 mL of 0.03% solution.
If you are trying to find the percentage, and only the percentage. The answer would be to divide 62 by 100 making 0.62. Then, times 0.62 by 1250. the answer is 775 students. If you are looking for the percentage. Please be kind if not.
If you factor it then your answer will be -3(-3z-5) if you simplify the answer is 9z+15