A score of 85 would be 1 standard deviation from the mean, 74. Using the 68-95-99.7 rule, we know that 68% of normally distributed data falls within 1 standard deviation of the mean. This means that 100%-68% = 32% of the data is either higher or lower. 32/2 = 16% of the data will be higher than 1 standard deviation from the mean and 16% of the data will be lower than 1 standard deviation from the mean. This means that 16% of the graduating seniors should have a score above 85%.
I would go with A but I am not 100% sure so you may want to check however you can.
Answer:
,
,
and 
Step-by-step explanation:
Here, x represents the number of hours Zoe spent running on her wheel and y represents the number of hours spent scratching her cage.
Julie was awoke for at least an hour running on her exercise wheel and scratching the of her cage.
⇒ 
She ran on her wheel at least twice as long as she scratched at the corners of her cage.
⇒ 
Also, She spent more than 1/4 hour running on her wheel.
⇒ 
And, we know that number of hours can not be negative.
⇒
Therefore, the complete system of inequality which shows the given situation is,
,
and
, 
Note: the feasible region ( covered by the given system) is shown in the below graph.