Answer
Yes, the requirements for a hypothesis test are satisfied.
Work Step by Step
The requirements of a hypothesis test are:
1. The sample must be simple random.
2. The number of successes and failures must be greater than 10.
The children were selected randomly and are independent variables in the study, therefore the 1st requirement is fulfilled.
In the treatment group, 33 developed polio. In the placebo group, 115 developed polio. Therefore, the 2nd requirement is fulfilled.
Because both requirements for the hypothesis test were fulfilled, the answer is yes.