Answer:
495 milliliters of the 95% mixture are needed.
Step-by-step explanation:
Given that I need a 90% alcohol solution, and on hand I have a 55 ml of a 45% alcohol mixture, and I also have 95% alcohol mixture, to determine how much of the 95% mixture will I need to add to obtain the desired solution, the following calculation must be performed:
55 x 0.45 + 45 x 0.95 = 67.5
25 x 0.45 + 75 x 0.95 = 82.5
15 x 0.45 + 85 x 0.95 = 87.5
10 x 0.45 + 90 x 0.95 = 90
10 = 55
90 = X
90 x 55/10 = X
4,950 / 10 = X
495 = X
Thus, 495 milliliters of the 95% mixture are needed.
Answer:
-9j+5
combine like terms to get this answer
For this case what you must do is to determine the value of r of the given equation:
A = pi * r ^ 2.
Clearing the value of r we have:
r = root (A / pi)
Note that r has two roots:
r1: = + root (A / pi)
r2: = - root (A / pi)
In this case we must ignore the negative root.
Answer:
The formula to find r is
r = root (A / pi)
