Upper bound of probability Suppose we are testing 20 drugs and use a significance value of 0.01 in each test. Suppose at least one out of the 20 tests rejects the null hypothesis. What is the upper bound for the probability that declaring the corresponding drug useful is a type I error (i.e. reject null hypothesis when one should not)?
I am confused on where to start. Any help is appreciated

Hints:


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*If the null hypothesis is true, what is the probability of a particular test getting a significant result? 

*If the null hypothesis is true, what is the probability of a particular test not getting a significant result? 

*If the null hypothesis is true, what is the probability of all 20 tests not getting a significant result? 

*If the null hypothesis is true, what is the probability of at least one out of the 20 tests  getting a significant result and the  null hypothesis  is rejected?
I suppose the "upper bound" is because the answer to the first question is "less than or equal to $0.01$" rather than "exactly $0.01$".  You may also need an independence assumption.
Remember to worry about green jelly beans
