A scientist needs to make 2 liters of saline solution (salt water), in which the salt level must be at 15% concentration (meaning 15% of the water is salt).
Unfortunately, the scientist only has two types of saline solution in his
possession. He has saline solution with a 10% concentration level and saline
solution with a 35% concentration level.
10
How much of each type of saline solution should the scientist mix together to
achieve 2 liters of saline solution at a concentration level of 15%?
11
Let I represent the amount 10% saline solution and let y represent the amount
of 35% saline solution.
12
13

1.60 L of 10% solution

0.40 L of 35% solution

Step-by-step explanation:

If x = amount of 10% saline solution, and y = amount of 35% saline solution, then:

x + y = 2

0.10x + 0.35y = 0.15(2)

Solve with substitution:

0.10x + 0.35(2 − x) = 0.15(2)

0.10x + 0.70 − 0.35x = 0.30

0.40 = 0.25x

x = 1.60

y = 0.40

b: |12 – x| ≤ 0.25

step-by-step explanation:      

let x be the possible lengths in inches, of the ribbons jaime cut.

we have been given that jaime is cutting strips of ribbon for a project. he tries to cut each piece to be 12 inches long, but sometimes he cuts it too long or too short by as much as 0.25 inch.  

we can represent this information in an inequality as:

by the definition of absolute value function we will get,

upon combining our inequalities we will get,

therefore, the inequality   describes all the possible lengths (x), in inches, of the ribbons jaime cut.

step-by-step explanation:

addition

step-by-step explanation: