Answer:
240 ml of 1.5% solution and 360 ml of 4% solution should be used.
Step-by-step explanation:
Since a lab assistant needs to create a 600 mL mixture that is 3% hydrochloric acid, and the assistant has solutions of 1.5% and 4% in supply at the lab, to determine the number of milliliters of the 1.5% solution and the number of milliliters of the 4% solution that must be used, the following calculations must be performed:
50 x 0.015 + 50 x 0.04 = 0.75 + 2 = 2.75
40 x 0.015 + 60 x 0.04 = 0.6 + 2.4 = 3
600 x 0.4 = 240
Therefore, 240 ml of 1.5% solution and 360 ml of 4% solution should be used.
x+y=120_______1
x=4*y_________2
x=4y
substitute 4y for x in equation 1
`4y+y=120
5y=120
eliminate the coefficient of y
y=120/5
y=24
now,input 24 for y in equation 2
`x=4y
x=4*24
x=96
thus, the numbers are
96 and 24
