In a poll conducted by the Gallup organization in April 2013, 48% of a random sample of 1022 adults in the U. S. responded that they felt that economic growth is more important than protecting the environment. We can use this information to calculate a 95% confidence interval for the proportion of all U. S. adults in April 2013 who felt that economic growth is more important than protecting the environment. Make sure to include all steps.

The  95% confidence interval is  

Step-by-step explanation:

From the question we are told that  

     The sample proportion is

      The sample size is

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 z-table , the value is

The reason we are obtaining critical value of     instead of     is because  

  represents the area under the normal curve where the confidence level interval (   ) did not cover which include both the left and right tail while     is just the area of one tail which what we required to calculate the margin of error

NOTE: We can also obtain the value using critical value calculator (math dot armstrong dot edu)

    Generally the margin of error is mathematically represented as

substituting values

The 95% confidence interval is mathematically represented as

substituting values

24

step-by-step explanation:

the graph shows 30% of students walk. 80 students were questioned, so the number that said they walk is

30% × 80 = 0.30 × 80 = 24