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# Calculating a z interval for a proportion

AP.STATS: UNC‑4 (EU), UNC‑4.D (LO), UNC‑4.D.1 (EK), UNC‑4.D.2 (EK)
You might need: Calculator,Z table

## Problem

Fatimah wants to estimate the proportion of students at her school who ate breakfast every day last week. She takes an
SRS
of 80 of the 1000 students at her school and finds that 20 of those sampled ate breakfast every day last week.
Based on this sample, which of the following is a 95, percent confidence interval for the proportion of all students at the school who ate breakfast every day last week?