Answer: 0.0775
Step-by-step explanation:
Given : Mean : 
Standard deviation : 
Sample size : 
Since its normal distribution , then the formula to calculate the z-score is given by :-

For x= 28.2 hours

For x= 30 hours

The P- value = 

Hence, the probabiliy that the average time spent stydying for the sampe was between 28.2 and 30 hours = 0.0775
Answer:
-8
Step-by-step explanation:
3+8+8-2=17
7+4+5+1=17
10+12+3+x=17
x=17-25
=-8
Answer:
your answer is b. 18.84ft
Step-by-step explanation: