This is all you have to do.
Answer:
Joe is 14.
Martha is 28.
Step-by-step explanation:
Use the variables and information from the question to make equations.
If Joe's age is half Martha's:
(1/2)m = j OR 2j = m
If their ages combined is 42:
m + j = 42
We can substitute the equation m=2j into equation m + j = 42, replacing "m".
m + j = 42 Substitute m for 2j
2j + j = 42 Combine like terms, terms with same varables
3j = 42 Divide both sides by 3 to isolate j
j = 14 Joe's age
Since j = 14, we can substitute it into equation m=2j to find "m".
m = 2j Substitute j for 14
m = 2(14) Simplify
m = 28 Martha's age
Therefore Joe is 14 and Martha is 28.
if the sphere has a diameter of 5, then its radius is half that, or 2.5.
![\bf \textit{volume of a sphere}\\\\ V=\cfrac{4\pi r^3}{3}~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=2.5 \end{cases}\implies V=\cfrac{4\pi (2.5)^3}{3}\implies V=\cfrac{62.5\pi }{3} \\\\\\ V\approx 65.44984694978736\implies V=\stackrel{\textit{rounded up}}{65.45}](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bvolume%20of%20a%20sphere%7D%5C%5C%5C%5C%20V%3D%5Ccfrac%7B4%5Cpi%20r%5E3%7D%7B3%7D~~%20%5Cbegin%7Bcases%7D%20r%3Dradius%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20r%3D2.5%20%5Cend%7Bcases%7D%5Cimplies%20V%3D%5Ccfrac%7B4%5Cpi%20%282.5%29%5E3%7D%7B3%7D%5Cimplies%20V%3D%5Ccfrac%7B62.5%5Cpi%20%7D%7B3%7D%20%5C%5C%5C%5C%5C%5C%20V%5Capprox%2065.44984694978736%5Cimplies%20V%3D%5Cstackrel%7B%5Ctextit%7Brounded%20up%7D%7D%7B65.45%7D)
Answer:
25% off - savings of $11.25
Step-by-step explanation:
To find discount percentage = ((List price - sale price) / List price) * 100
(3.49+4.71)1.80=cost
(8.2)1.80=cost
14.76=cost
Luis spends $14.76 all together