Ana, this is the solution to the exercise:
Part A
• Point Estimate = Number of successes/Sample size
,
• Point Estimate = 22/74
,
• Point Estimate = 0.297
,
• Point Estimate = 0.3 (Rounding to the next tenth)
Part B
p = 0.3
1 - p = 0.7
Margin of error = +/- 3.1% = 0.031
Using the formula for calculating the interval we have:
0.3 +/- 0.031
• Lower limit = 0.3 - 0.031 = 0.269
,
• Upper limit = 0.3+ 0.031 = 0.331
Statement: Based on the data provided, the confidence interval is:
0.269 < p < 0.331, with a margin of error of 3.1%