Pessimist Singularitarian

#2
December 21st, 2016,
02:36
I've edited the title of your thread to indicate the nature of the question being asked.

To find the cost per day for the first 92 days, which we'll call$C_1$, we need to take the total cost and divide by the total number of days.:

$ \displaystyle C_1=\frac{5980\text{ dollars}}{92\text{ days}}=65\,\frac{\text{dollars}}{\text{day}}$

Now, to find how much more that 1 additional day costs, we find the difference $D$ between the cost for that additional day and the average cost for the first 92 days:

$ \displaystyle D=\left(97-65\right)\,\frac{\text{dollars}}{\text{day}}=32\,\frac{\text{dollars}}{\text{day}}$