The interest figure always means the interest for a year.
120 days is 1/3 of a year, so you'll only earn 1/3 of 6.5% .
6.5% = 0.065
1/3 of that is 0.02167 .
(0.02167) x (7,000) = 151.67
Solve for x by cross multiplication
- Swap the sides of equation
- Divide both sides of equation by 30
Answer:
40 copies for $3000
Step-by-step explanation:
First: The Equation
y=(20+x)(100-x)
This shows how for every new painting, the price will go down.
y=2000+80x-x²
Convert it to standard form: ax²+bx+c
You can now choose to graph it or find the vertex form. For the limit of time, I will just use a graph.
The vertex, (40,3000), is your answer, where the x value is the number of paintings and the y value the money made.