To find your sale price you must:

just simply follow that operation and you're good to go
There was a
66
% increase from Sari's sales from November to December.
To find the percentage increase in her sales, we must first find the amount her sales increased. We can do that by subtracting the greeting cards sold in November from the number of greeting cards sold in December. Substituting values and simplifying, we get that she sold 200 more greeting cards in December.
To find what percent increase this is, we must find what percent 200 is of the number of greeting cards sold in November. We can do this by dividing 200 by the number of cards sold in November (300), and then multiplying by 100 (to make it a percent). Doing this, we get

* 100 which gives us our answer of
66
%.
Answer:
Mean=50.
standard deviation=50.
Step-by-step explanation:
Let the perfect score be 100.
The mean(average) of a data is given by: 
Here the number of data points are 100. out of which 50 attains a value 100,and 50 attains value 0.
so, sum of data points=50×100+50×0=5000.

Mean=50.
"Now the standard deviation of data points are calculated by firstly subtracting mean from every entry and then square the number and take it as new entry and calculate the mean of the new data entry and lastly taking the square root of this new mean".
Here if 50 is subtracted from each entry the new entry will have 50 entries as '50' and 50 entries as '-50'.
next on squaring we will have all the 100 entries as '2500'.
now the mean of these entries is: 
=2500
taking it's squareroot we have 
Hence, standard deviation=50.
No, 43 is a prime number, so that statement is false.
I belive the answer is no. Tell me if im doing this wrong, but the square root of 380 is a decimal number.