Answer:
95%
Step-by-step explanation:
In this case we can apply a formula that tells us that:
# (AUB) = #A + #B - #AnB
Where A would be the ones who enjoy swimming and B would be the ones who enjoy running. AnB is the intersection of both sets, that is, those who enjoy doing both things, these values we have, if we replace them we have left:
#(AUB) = 80% + 70% - 55%
#(AUB) = 95%
Which means that 95% of people enjoy either swimming or running
a = amount invested at 5%
b = amount invested at 2%
now, we know the total invested by Mr Wilson was 20000, so whatever "a" and "b" might be, we know that a + b = 20000.
![a + b = 20000\implies b = 20000-a \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{5\% of a}}{\left( \cfrac{5}{100} \right)a}\implies 0.05a~\hfill \stackrel{\textit{2\% of b}}{\left( \cfrac{2}{100} \right)a}\implies \begin{array}{llll} 0.02b\\\\ \stackrel{substituting}{0.02(20000-a)} \end{array}](https://tex.z-dn.net/?f=a%20%2B%20b%20%3D%2020000%5Cimplies%20b%20%3D%2020000-a%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7B5%5C%25%20of%20a%7D%7D%7B%5Cleft%28%20%5Ccfrac%7B5%7D%7B100%7D%20%5Cright%29a%7D%5Cimplies%200.05a~%5Chfill%20%5Cstackrel%7B%5Ctextit%7B2%5C%25%20of%20b%7D%7D%7B%5Cleft%28%20%5Ccfrac%7B2%7D%7B100%7D%20%5Cright%29a%7D%5Cimplies%20%5Cbegin%7Barray%7D%7Bllll%7D%200.02b%5C%5C%5C%5C%20%5Cstackrel%7Bsubstituting%7D%7B0.02%2820000-a%29%7D%20%5Cend%7Barray%7D)
now, we know the total of earned interest is 550 bucks, so then

Answer:
= 3052.08 cm^3
Step-by-step explanation:
Volume of a sphere is given by
V = 4/3 pi r^3
We know the diameter is 18
d = 2r
18 = 2r
Divide each side by 2
18/2 =2r/2
9 =r
V = 4/3 pi 9^3
V = 4/3 pi (729)
V = 972 pi
Approximating pi by 3.14
V =972 (3.14)
= 3052.08 cm^3