Downloaded Photomath it’s going to help you a lot, and show you step by step, also it’s free.
Answer:
4 lbs left after 5 days
Step-by-step explanation:
First, you need to step up an equation!
You know that Soomin has a total of 20 pounds and that she's using it, so you are going to use subtraction.
She uses 3 1/5 pounds per day so you write:
20 - 3 1/5x
and you know that she wants to know how much she has left after 5 days so you replace the x with 5:
20 - (3 1/5) * 5
Multiply first:
20 - 16
After Subtracting you get the answer:
4 lbs left
Answer:

Step-by-step explanation:
If
, then
. It follows that
![\begin{aligned} \\\frac{g(x+h)-g(x)}{h} &= \frac{1}{h} \cdot [g(x+h) - g(x)] \\&= \frac{1}{h} \left( \frac{1}{x+h} - \frac{1}{x} \right)\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%5C%5C%5Cfrac%7Bg%28x%2Bh%29-g%28x%29%7D%7Bh%7D%20%26%3D%20%5Cfrac%7B1%7D%7Bh%7D%20%5Ccdot%20%5Bg%28x%2Bh%29%20-%20g%28x%29%5D%20%5C%5C%26%3D%20%5Cfrac%7B1%7D%7Bh%7D%20%5Cleft%28%20%5Cfrac%7B1%7D%7Bx%2Bh%7D%20-%20%5Cfrac%7B1%7D%7Bx%7D%20%5Cright%29%5Cend%7Baligned%7D)
Technically we are done, but some more simplification can be made. We can get a common denominator between 1/(x+h) and 1/x.

Now we can cancel the h in the numerator and denominator under the assumption that h is not 0.

Answer:
22.5%
Step-by-step explanation:
The total number of students in percentage terms is 100%
Students that chose others = 100% - 40% - 37.5% = 22.5%
0.77875...
which, I'm assuming, they want you to round to the nearest hundredth? So, .78?...