Statistics help, please!

Mean: 81
Median: 83
Mode: 80
Standrard Deviation: 9
First Quartile: 60
3rd Quartile: 89
90th precentile: 95

 

1. What score did half of the students exceed?

 

2. About what percent of the students’ grades exceeded 89?

 

3. About what percent of students’ grades were less than 95?

 

4. If there were 100 students enrolled in the class what would be the total of all the scores?

 

5.What test score represents one standard deviation above the mean?

 

6. What test score represents 1.5 standard deviations below the mean?

 

*** The other 4 questions are based on this:***

 

The average price for a medium cup of coffee in the Center Town is normally distributed with a mean of $1.95 and a standard deviation of $0.23.

 

1.) What percent of cups of coffee sold were between $1.75 and $2.15?

 

2.) What percent of cups of coffee were sold for greater than $1.50?

 

3.) What percent of cups of coffee were sold for greater than $2.00?

 

4.) What percent of cups of coffee were sold for less than $2.20?