Answer:
Last option
Step-by-step explanation:
Answer:
The approximate percentage of SAT scores that are less than 865 is 16%.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean of 1060, standard deviation of 195.
Empirical Rule to estimate the approximate percentage of SAT scores that are less than 865.
865 = 1060 - 195
So 865 is one standard deviation below the mean.
Approximately 68% of the measures are within 1 standard deviation of the mean, so approximately 100 - 68 = 32% are more than 1 standard deviation from the mean. The normal distribution is symmetric, which means that approximately 32/2 = 16% are more than 1 standard deviation below the mean and approximately 16% are more than 1 standard deviation above the mean. So
The approximate percentage of SAT scores that are less than 865 is 16%.
Answer:
one number= x = 44
the other number= (x-4)= 40
Step-by-step explanation:
one number= x
the other number= (x-4)
x + (x-4) = 84
2x= 84+4
2x= 88
x= 88/2= 44
one number= x = 44
the other number= (x-4)= 40
9514 1404 393
Answer:
a, b, c --- all <em>not</em> representative
Step-by-step explanation:
The question posed by the engineer is "are residents of the city in favor of ...".
The only representative sample is one from a pool that includes <em>all residents of the city</em>—not just those who (a) use the road, (b) live along the road, or (c) own homes.
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<em>Additional comment</em>
The engineer may want to refine the question. As posed, it would include children, homeless, and/or institutionalized residents of the city as well as drivers and tax-payers. In inclusive cultural traditions, "residents of the city" may also include animals, plants, water, air, and other holders of spiritual energy.
