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Calculating the test statistic in a z test for a proportion

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Jake heard that spinning—rather than flipping—a penny raises the probability above 50% 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 H0:p=0.50 versus Ha: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.
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi