Determine the analysis and state the null and alternate hypothesis.
Find out what analysis would you do on each problem (i.e., one-sample z-test, one-sample t-test, proportion test, two-sample independent t-test, or paired test)? After that state the null and alternative hypothesis for a problem.
Assume you have developed a new program to stop teens from smoking. You try the program on high school seniors and then learn how many of them started to smoke. You believe that the proportion of students smoking would be less than the current value of 23.