4 5/5; 3 10/5; 2 15/5, 1 20/5.
Answer:
We use ratio and proportion
If EC$ 2.50 = US$ 1.00
Then EC$ 20.00 = US$ 20 × 1 / 2.50
= US$ 8.00
Hope this helps
Answer:
Lorenzo's score on exam was 75.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 61
Standard Deviation, σ = 8
We are given that the distribution of test score is a bell shaped distribution that is a normal distribution.
Formula:
![z_{score} = \displaystyle\frac{x-\mu}{\sigma}](https://tex.z-dn.net/?f=z_%7Bscore%7D%20%3D%20%5Cdisplaystyle%5Cfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D)
z-score = 1.75
We have to find the value of x.
Putting values, we get
![1.75 = \dfrac{x - 61}{8}\\\\x = 1.75(8) + 61\\x = 75](https://tex.z-dn.net/?f=1.75%20%3D%20%5Cdfrac%7Bx%20-%2061%7D%7B8%7D%5C%5C%5C%5Cx%20%3D%201.75%288%29%20%2B%2061%5C%5Cx%20%3D%2075)
Thus, Lorenzo's score on exam was 75.
Answer: There will enough to paint the outside of a typical spherical water tower.
Step-by-step explanation:
1. Solve for the radius r from the formula for calculate the volume of a sphere. as following:
![V=\frac{4}{3}r^{3}\pi\\\frac{3V}{4\pi}=r^{3}\\r=\sqrt[3]{\frac{3V}{4\pi}}](https://tex.z-dn.net/?f=V%3D%5Cfrac%7B4%7D%7B3%7Dr%5E%7B3%7D%5Cpi%5C%5C%5Cfrac%7B3V%7D%7B4%5Cpi%7D%3Dr%5E%7B3%7D%5C%5Cr%3D%5Csqrt%5B3%5D%7B%5Cfrac%7B3V%7D%7B4%5Cpi%7D%7D)
2. Substitute values:
![r=\sqrt[3]{\frac{3(66,840.28ft^{3})}{4\pi}}=25.17ft](https://tex.z-dn.net/?f=r%3D%5Csqrt%5B3%5D%7B%5Cfrac%7B3%2866%2C840.28ft%5E%7B3%7D%29%7D%7B4%5Cpi%7D%7D%3D25.17ft)
3. Substitute the value of the radius into the equation fo calculate the surface area of a sphere, then you obtain that the surface area of a typical spherical water tower is:
![SA=4r^{2}\pi\\SA=4(25.17ft)^{2} \pi\\SA=7,964.95ft^{2}](https://tex.z-dn.net/?f=SA%3D4r%5E%7B2%7D%5Cpi%5C%5CSA%3D4%2825.17ft%29%5E%7B2%7D%20%5Cpi%5C%5CSA%3D7%2C964.95ft%5E%7B2%7D)
3. If a city has 25 gallons of paint available and one gallon of paint covers 400 square feet of surface area, you must multiply 25 by 400 square feet to know if there will be enough to paint the outside of a typical spherical water tower.
![25*400ft^{2}=10,000ft^{2}](https://tex.z-dn.net/?f=25%2A400ft%5E%7B2%7D%3D10%2C000ft%5E%7B2%7D)
As you can see, there will enough to paint the outside of a typical spherical water tower.