Answer:
16% probability that a randomly chosen U.S. adult sleeps more than 8.7 hours per night
Step-by-step explanation:
The Empirical Rule(Standard Deviation) states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 7.5
Standard deviation = 1.2
Using the Standard Deviation Rule, what is the probability that a randomly chosen U.S. adult sleeps more than 8.7 hours per night?
8.7 = 7.5 + 1.2
So 8.7 is one standard deviation above the mean.
By the Empirical Rule, 68% of the measures are within 1 standard deviation of the mean. The other 100-68 = 32% are more than one standard deviation from the mean. Since the normal probability distribution is symmetric, 16% are more than one standard deviation below the mean and 16% are more than one standard deviation above the mean(above 8.7 hours)
So, 16% probability that a randomly chosen U.S. adult sleeps more than 8.7 hours per night
Can see it can you make it bigger
Answer:
C. The interquartile range is 55
Step-by-step explanation:
When you want to find the interquartile range you look at the box plot to see that it is everything from the upper interquartile range to the lower interquartile range is the interquartile range. So from 40 to 65. So there for the answer C. is incorrect.
