Answer:
The correct Answer is 0.0571
Explanation:
53% of U.S. households have a PCs.
So, P(Having personal computer) = p = 0.53
Sample size(n) = 250
np(1-p) = 250 * 0.53 * (1 - 0.53) = 62.275 > 10
So, we can just estimate binomial distribution to normal distribution
Mean of proportion(p) = 0.53
Standard error of proportion(SE) = 
= 
= 0.0316
For x = 120, sample proportion(p) = 
= 
= 0.48
So, likelihood that fewer than 120 have a PC
= P(x < 120)
= P( p^ < 0.48 )
= P(z < 
) (z=
)
= P(z < -1.58)
= 0.0571 ( From normal table )
Answer:
While the developed world benefits from the modern explosion of technology, countries like Ethiopia continue to rely on their forefathers' methods for important daily tasks such as farming, cooling, and providing clean water. These activities are often physically challenging, time and energy intensive, and are often carried out by female family members in many such societies. Furthermore, they can damage the local ecology and climate, such as deforestation and soil erosion caused by the use of trees for firewood. Western technologies are often too complicated, expensive, unacceptable, and difficult to maintain in developing societies, so they are of little or no use in these situations.
Answer:
The answer is "
"
Explanation:
Calculating the mean for brand A:
Calculating the Variance for brand A:
Calculating the Standard deviation:
Calculating the Mean for brand B:
Calculating the Variance for brand B:
Calculating the Standard deviation:
