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Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?

Solve for n? [tex]z = \frac{3}{4} mn[/tex]

Charlie tosses five coins.what is the probability that all five coins will land tails up.