The required expression is 100 - 0.2w
Step-by-step explanation:
Given,
Amount of radioactive substance = 100 mg
The substance decreases by 20% each week.
To find the remaining amount of the in w weeks.
Now,
Each week 20% = 0.2 of the substance will be decreased.
So, in w weeks 0.2×w of the the substance will be decreased.
Hence,
The remaining substance = 100 - 0.2w
Answer:
b
Step-by-step explanation:
Answer:

Step-by-step explanation:
<h3>to understand this</h3><h3>you need to know about:</h3>
<h3>given:</h3>
<h3>to find:</h3>
<h3>let's solve:</h3>

A-5B=2x+3-5(x²-5x+1)

- distribute -5 to the parentheses:2x+3-5x²+25x-5
- rewrite:-5x²+2x+25x-5+3
- combine like terms:-5x²+27x-2
and
we are done
Answer:
20
Step-by-step explanation:
4 Cup's = 1 Quarter so do
4 x 5 because that is how many quarters you have and that is how you get the answer