Story: mr krabs created a secret ingredient for a breath mint that he thinks will "cure" the bad breath people get from eating crabby patties. he had 50 customers (group a) ear a breath mint after they finish eating. the other 50 customers (group b) also recieved a breath mint after eating, however it was just a regular breath mint and did not have the secret ingredient. both groups were told they were getting the breath mint that would cure their bad breath. two hours after eating the crabby patties 30 customers in group a and 10 customers in group b reported havibg better breath then they normally had after eating pattiex.

question: why do you think 10 people in group b reported fresher breath?