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.
Simplify equation: 14 - 7y + 5 = 1 + 3y + 24
simplify again: 19 - 7y = 25 + 3y
add -25 and 7y to both sides: -6 = 10y
y = -6/10 or -0.6
2. After 30 minutes, richie has delivered 1/3 of the papers, so they have to deliver the remaining 2/3. Since they can deliver them all in 40 minutes, would the answer be 2/3 of 40? I'm not sure about this.
By hypothesis, Deon is riding at a speed of 22.4 kilometers per hour. So each hour, he completes 22.4 km.
If he rides for 7 hours, he completes 22.4 * 7 = 156.8 km
So in 7 hours, he rides 156.8 kilometers.
Hope this helps! :)