Google “slope calculator” on google
Use calculator soup.
Do 12 2/3+10 2/3 which is 23 1/3 than subtract 8 2/3 for your answer.
You just use what you already know. You know that 1 week is equal to 7 days so you just do 1 * 7 = 7 or 1 week. Then 54 * 7 = 378
As per the problem,
Rhonda bought a new laptop for $800.
The laptop depreciates, or loses, 20% of its value each year.
The value of the laptop at a later time can be found using the formula

Here we have
P=$800
r=20%=0.20
t=2 years
Substitute the values in equation (1) we get

The laptop be worth in two years will be $512.