ACTIVITY 7.2.3: Excel: Confidence intervals for a proportion. Click this link to download the spreadsheet for use in this activity. Critical values for quick reference during this activity. Confidence level | Critical value 0.90 2* = 1.645 0.95 2* = 1.960 0.99 2* = 2.576 414214.2653566.qx3z Jump to level 1 A hunger relief organization is trying to determine the lowest likely proportion of the local population that lives within two miles of a grocery store. A random sample of 50 local citizens was polled. Use Sheet 4 of the Excel file linked above to calculate p and the 95% confidence interval. p = Ex: 1.234 9 Upper bound for 95%% confidence interval = Ex: 1.234 Lower bound for 95% confidence interval = The organization can say with 95% confidence that the true population proportion of the local population that lives within two miles of a grocery store is in the interval [ Ex: 1.234 The lowest likely proportion is Ex: 1.234