1) A and B are among 6 participants in a bike race. If no two participants finish the race at the same time and A must finish the race before B, how many different possible orders of finishing are there?
If there are 6 participants there will be 6! = 720 orders without any restriction. Now either A has to come before B or after B. Both have equal chances. Therefore number of ways in which A finishes before B =720/2 = 360
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