Allison needs 18 liters of 5% saline solution. She has a 1% solution available. How many liters of the 1% solution and how many liters of the 10%solution should she mid to make the 5% solution

10 litres of 1% solution and 8 litres of 10% solution

Step-by-step explanation:

Let volume of 1% solution = x

So volume of 10% solution = 18 - x

5% of 18 litres = 0.9

Equation formed is

x * (1/100) + (18 - x) * (10/100) = 0.9

x + (18 - x) 10 = 0.9 * 100

x + 180 - 10x = 90

-9x = 90 - 180

-9x = - 90

x = 10 litres

10 litres of 1% solution and 8 litres of 10% solution