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## AP®︎/College Statistics

### Course: AP®︎/College Statistics>Unit 10

Lesson 5: Carrying out a test for a population proportion

# Calculating the test statistic in a z test for a proportion

You might need: Calculator

## Problem

Jake heard that spinning—rather than flipping—a penny raises the probability above $50\mathrm{%}$ that the penny lands showing heads. He tests this by spinning $10$ different pennies $10$ times each, so he's willing to treat these spins as a random sample. In his $100$ spins, the penny landed showing "heads" in $68$ spins. He wants to use these results to test ${H}_{0}:p=0.50$ versus ${H}_{\text{a}}:p>0.50$, where $p$ is the true proportion of spins that a penny would land showing "heads".
Assuming that the conditions for inference have been met, calculate the test statistic for Jake's significance test.
You may round to two decimal places.
$z=$
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