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: c) 0.531441 = 0.53
e) 3.375 = 3.38 or 3.4
f)0.0289 =0.03
Step-by-step explanation: everyone will say that they will mark as brainliest but nobody does, you guys lie, but I still give the answers
I am almost positive that it is 360
Answer:
Step-by-step explanation:
Givens
pi = 3.14
d = 3.8
r = d/2
r = 3.8/2 = 1.9
Formula
V = (4/3) * pi * r^3
Solution
V = (4/3) * 3.14 * 1.9^3
V = 4/3 * 3.14 * 6.859
V = 28.7163
Answer:
1) decay
2) growth
3) growth
Step-by-step explanation:
A generic exponential function can be written as:
f(x) = A*(r)^x
Where:
A is the initial amount of something.
r is the rate of growth.
x is the variable, usually, represents time.
if r > 1, we have an exponential growth.
if r < 1, we have an exponential decay.
1) f(x) = (3/4)^x
in this case we have:
A = 1
r = (3/4) = 0.75
Clearly, r < 1.
Then this is an exponential decay.
2) f(x) = (1/6)*4^x
In this case we have:
A = (1/6)
r = 4
Here we have r > 1.
Then this is an exponential growth.
3) f(x) = (1/4)*(5/2)^x
in this case we have:
A = 1/4
r = 5/2 = 2.5
here we have r > 1, then this is an exponential growth.
