Answer:
So, the probability is P=0.094.
Step-by-step explanation:
We know that in a recent survey, 73% of the community favored building a police substation in their neighborhood.
We get that p=0.73 and q=1-0.73=0.27.
We calculate the probability that exactly 8 of them favor the building of the police substation, if 14 citizens are chosen.
We get that n=14 and k=8.
We calculate the probability:
So, the probability is P=0.094.
Answer:
68% of the sample can be expected to fall between 28 and 32 cm
Step-by-step explanation:
The Empirical Rule 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 = 30
Standard deviation = 2
What proportion of the sample can be expected to fall between 28 and 32 cm
28 = 30-2
28 is one standard deviation below the mean
32 = 30 + 2
32 is one standard deviation above the mean
By the Empirical Rule, 68% of the sample can be expected to fall between 28 and 32 cm
Given:
The price of a doll = $35
Sales tax = 6%
To find:
The tax amount that a customer will pay on one doll.
Solution:
The price of doll is $35 and the sales tax is 6%, so the tax amount on a doll is 6% of 35.
Therefore, the tax amount that a customer will pay on one doll is $2.1.
Answer:
9 hours, 20 minutes
Step-by-step explanation:
When two ferries work together, they transport a day's cargo in 7 hours
The speed proportion or ratio of larger ferry to smaller ferry is given as 3 : 1
The sum of the ratio = 4 (3 + 1)
This means that it will take the smaller ferry = 7 x 4 hours to work alone = 28 hours, since the larger ferry is faster by 3.
Therefore, when larger ferry works alone, it will take it (7 x 4)/3 = 9.33 hours.
9.33 hours = 9 hours, 20 minutes.
