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:
He needs to work for a minimum of 4 weeks
Step-by-step explanation:
Amount he has saved=$375
Amount he needs to earns to buy a dirt bike=He earns $155 per week=155×Number of weeks he's worked(N)
This can be expressed as;
The total amount he earns=(Amount saved)+(Amount he earns per week)
Where;
Amount he needs to earn to buy a dirt bike=$900
Amount saved=$375
Amount he earns per week=155N
Replacing in the expression above
900=375+155N
900-375=155N
525/155=155N/155
N=3.4 weeks
Number of weeks=N=3.4 weeks
Minimum Number of weeks he needs to work=4 weeks
Answer:
one mile per hour
Step-by-step explanation: