Answer:
H0 : p = 0.5
H1 : p ≠ 0.5
Two tailed test
Step-by-step explanation:
The test if the true proportion of heads is different from 50%; this means the initial truth, that is the true proportion is 50% ; which is the null ;
H0 : p = 0.5
The researcher intends to test if the true proportion is not 50% ; that is the researcher is n spwcudfic about if the proportion is lower or higher, he just wants to test that the proportion is different, hence the test could go either way ;
Alternative hypothesis ;
H1 : p ≠ 0.5
Since the sign in the alternative hypothesis could be in either direction, then we have a two tailed test