Answer:
$210
Step-by-step explanation:
The first thing we can do is to add the $25 back on to the total cost.
25 + 115 = 140.
We do this because he Sam used a gift certificate on the ski's that are already 2/3 of the original price.
Now, to find the original price we can use this equation:

X represents the original price.
To solve this equation you would flip 2/3 to 3/2 and multiply that by 140, as seen below:

Now you can solve:

We can check this answer by multiplying 210 by 2/3
(210)(2/3) = 140
Remember, Sam used a gift certificate for $25
140 - 25 = $115
Therefore, the original price of the skis is $210.
<em>I hope this helps!!</em>
<em>- Kay :)</em>
Answer:
The hourly decay rate is of 1.25%, so the hourly rate of change is of -1.25%.
The function to represent the mass of the sample after t days is 
Step-by-step explanation:
Exponential equation of decay:
The exponential equation for the amount of a substance is given by:

In which A(0) is the initial amount and r is the decay rate, as a decimal.
Hourly rate of change:
Decreases 26% by day. A day has 24 hours. This means that
; We use this to find r.



![\sqrt[24]{(1-r)^{24}} = \sqrt[24]{0.74}](https://tex.z-dn.net/?f=%5Csqrt%5B24%5D%7B%281-r%29%5E%7B24%7D%7D%20%3D%20%5Csqrt%5B24%5D%7B0.74%7D)



The hourly decay rate is of 1.25%, so the hourly rate of change is of -1.25%.
Starts out with 810 grams of Element X
This means that 
Element X is a radioactive isotope such that its mass decreases by 26% every day.
This means that we use, for this equation, r = 0.26.
The equation is:



The function to represent the mass of the sample after t days is 
Answer: m= -1/8
Good luck !
Answer:
The greater than symbols looks like this > , and the less than symbol looks like? <