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greece has faced a severe economic crisis since the end of 2009. a gallup poll surveyed 1,000 randomly sampled greeks in 2011 and found that 25% of them said they would rate their lives poorly enough to be considered "suffering."

1 Answer

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Answer:

a

The population parameter of interest is the true proportion of Greek who are suffering

While the point estimate of this parameter is proportion of those that would rate their lives poorly enough to be considered "suffering". which is 25%

b

The condition is met

c

The 95% confidence interval is

d

If the confidence level is increased which will in turn reduce the level of significance but increase the critical value() and this will increase the margin of error( deduced from the formula for margin of error i.e ) which will make the confidence interval wider

e

Looking at the formula for margin of error if the we see that if the sample size is increased the margin of error will reduce making the confidence level narrower

Step-by-step explanation:

From the question we are told that

The sample size is n = 1000

The population proportion is

Considering question a

The population parameter of interest is the true proportion of Greek who are suffering

While the point estimate of this parameter is proportion of those that would rate their lives poorly enough to be considered "suffering". which is 25%

Considering question b

The condition for constructing a confidence interval is

So

Hence the condition is met

Considering question c

Given that the confidence level is 95% then the level of significance is mathematically evaluated as

Next we obtain the critical value of from the normal distribution table, the value is

Generally the margin of error is mathematically represented as

substituting values

The 95% confidence interval is mathematically represented as

substituting values

substituting values

considering d

If the confidence level is increased which will in turn reduce the level of significance but increase the critical value() and this will increase the margin of error( deduced from the formula for margin of error i.e ) which will make the confidence interval wider

considering e

Looking at the formula for margin of error if the we see that if the sample size is increased the margin of error will reduce making the confidence level narrower

User Artem Ilchenko
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