Answer:
$64.32
Step-by-step explanation:
What you do is:
$53.60×20% → $53.60×0.2
$53.60×0.2=$10.72
$10.72 is the amount of money taken off because of the sale.
Then what you do is:
$53.60+$10.72=_____
53.60
<u>+10.72</u>
64.32
The original price was $64.32.
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Answer:
900 sample size
Step-by-step explanation:
To determine the sample size for a proportion, the margin of error formula is used to determine this:
Where p is the proportion, E is the margin of error, n is the sample size, q = 1 - p, 
is the z score.
Since the proportion is not known, the sample size needed to guarantee the confidence interval and error is at p = 0.5 and q = 1 - p = 1 - 0.5 = 0.5
E = 5% = 0.05, = 3. Hence:
The <em>total</em> area of all six faces of the tunnel is 
square centimeters.
<h2>Procedure - Surface area of a tunnel for a toy train</h2>
The surface area of the solid (
) used to represent the tunnel for a toy train is the sum of its six faces (two <em>semicircular</em> sections, inner <em>semicircular</em> arc section, outer <em>semicircular</em> arc section, two rectangles).
<h3>Determination of the surface area of the tunnel based on information of the diagram</h3>
We calculate the surface area as following:
![A = 2\cdot \frac{\pi}{2} \cdot [(10\,cm)^{2}-(8\,cm)^{2}] + \pi\cdot (8\,cm)\cdot (30\,cm) + \pi\cdot (10\,cm)\cdot (30\,cm) + 2\cdot (2\,cm)\cdot (30\,cm)](https://tex.z-dn.net/?f=A%20%3D%202%5Ccdot%20%5Cfrac%7B%5Cpi%7D%7B2%7D%20%5Ccdot%20%5B%2810%5C%2Ccm%29%5E%7B2%7D-%288%5C%2Ccm%29%5E%7B2%7D%5D%20%2B%20%5Cpi%5Ccdot%20%288%5C%2Ccm%29%5Ccdot%20%2830%5C%2Ccm%29%20%2B%20%5Cpi%5Ccdot%20%2810%5C%2Ccm%29%5Ccdot%20%2830%5C%2Ccm%29%20%2B%202%5Ccdot%20%282%5C%2Ccm%29%5Ccdot%20%2830%5C%2Ccm%29)
The <em>total</em> area of all six faces of the tunnel is square centimeters. 
To learn more on surface areas, we kindly invite to check this verified question: brainly.com/question/2835293
Answer:
Step-by-step explanation:
First, note this parameters from the question.
We let x = number of $5 increases and number of 10 decreases in plates sold.
Our Revenue equation is:
R(x) = (300-10x)(10+5x)
We expand the above equation into a quadratic equation by multiplying each bracket:
R(x) = 3000 + 1500x - 3000x - 1500x^2
R(x) = -1500x^2 - 1500x + 3000 (collect like terms)
Next we simplify, by dividing through by -1500
= 1500x^2/1500 - 1500x/1500 + 3000/1500
= X^2 - x + 2
X^2 - x + 2 = 0
Next, we find the axis of symmetry using the formula x = -b/(2*a) where b = 1, a = 1
X = - (-1)/2*1
X = 1/2
Number of $5 increases = $5x1/2 = $2.5
=$2.5 + $20 = $22.5 ticket price gives max revenue.
The answer to your question is 448in squared
