A lab assistant needs to create a 600 mL mixture that is 3% hydrochloric acid. The assistant has solutions of 1.5% and 4% in supply at the lab. Using the variables x and
y to represent the number of milliliters of the 1.5% solution and the number of
milliliters of the 4% solution respectively, determine a system of equation that
describes the situation.

Enter the equations below separated by a comma.

How many milliliters of the 1.5% solution should be used?

How many milliliters of the 4% solution should be used?

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.

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb

3,000,540

step-by-step explanation: