For the first one at the top it’s 300 and 575 then going down it’s 17.21, 63.33, and then 184.68
No because its explain how much cumulative tip total on day 5 so the answer is D.400
Answer:

Step-by-step explanation:
We know that for principal amount P , time period T and rate of interest
, simple interest is given by
.
Here ,

To find : simple interest rate i.e., 
On putting values of
in formula , we get 

Now we need to round off the answer to the nearest tenth .
So, simple interest rate is % =
=
The solution to the equation would be 21.5
Why?
If you do the equation backwards
30 - 8.5 = x
You would get 21.5
You can plug it into the first equation to check!
:)