Answer: choice A. 40 liters
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Explanation:
x = number of liters of the 50% alcohol solution
If we have x liters of 50% alcohol, then we have 0.50*x liters of pure alcohol. This is added to 0.90*40 = 36 liters of pure alcohol (from the 90% solution).
So far we have 0.50*x + 36. This expression represents the total amount of pure alcohol. We want a 70% solution, so we want 70% of the total 40+x meaning 0.50*x + 36 is to be set equal to 0.70*(40+x) and we solve for x as shown below
0.50*x + 36 = 0.70*(40+x)
0.50*x + 36 = 0.70*(40)+0.70*(x)
0.50*x + 36 = 28+0.70*x
36 - 28 = 0.70*x - 0.50x
8 = 0.20x
0.20x = 8
x = 8/0.20
x = 40
So that is why the answer is choice A. 40 liters
Answer:
I think it is either 1/6 or 1/8
Hope it helps :)
There are 12 inches in 1 foot, and each bracelet takes 6 inches
12 divided by 6 = 2
there can be 2 bracelets per foot of yarn
5 x 2 = 10 bracelets can be made
let me know if you have any further questions
:)
Using the tangent rule:
Tangent(angle) = Opposite leg / Adjacent leg
We will use the 23 degree angle to solve for x.
Tangent(23) = X / 6
x = 6 * tangent(23)
x = 2.5
Simple, solve straight across, its either 4n or 2n