Solution:
Matte Satin Glossy Total
Homeowners 0.08 0.20 0.24 0.52
Contractors 0.04 0.26 0.18 0.48
Total 0.12 0.46 0.42 1
Approximately what percentage of contractors prefer the glossy finish?
Answer: Percentage of contractors who prefer the glossy finish is:
or 
Therefore, the option D. 37.5% is correct
A vertical line on the value x = -4
After the donation,
3m + m = 132
manual = 33
digital = 99
Before the donation, he had 82 more digital and 26 more manual cameras.
82 + 99 = 181 digital
26 + 33 = 59 manual
For a double check, before donation,
digital + manual = 240
181 + 59 = 240
So, to begin with, the number of digital cameras = 181.
Set the whole expression = to 0 and solve for x.
3x^(5/3) - 4x^(7/3) = 0. Factor out x^(5/3): x^(5/3) [3 - 4x^(2/3)] = 0
Then either x^(5/3) = 0, or 3 - 4x^(2/3) = 0.
In the latter case, 4x^(2/3) = 3.
To solve this: mult. both sides by x^(-2/3). Then we have
4x^(2/3)x^(-2/3) = 3x^(-2/3), or 4 = 3x^(-2/3). It'd be easier to work with this if we rewrote it as
4 3
--- = --------------------
1 x^(+2/3)
Then
4
--- = x^(-2/3). Then, x^(2/3) = (3/4), and x = (3/4)^(3/2). According to my 3 calculator, that comes out to x = 0.65 (approx.)
Check this result! subst. 0.65 for x in the given equation. Is the equation then true?
My method here was a bit roundabout, and longer than it should have been. Can you think of a more elegant (and shorter) solution?