ProbabilityStep 1 of 3
Question
One number is chosen at random from 1 to 20. Find the probability that it is neither a multiple of 2 nor a multiple of 5.
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12 excluded
8 neither
How many numbers are multiples of 2 or 5?
What you will learn
Translate “neither” into a complement event and count non-overlapping excluded outcomes without double counting.
Common mistake to avoid
Students may treat “neither” as the union of the named events instead of subtracting that union from the full sample space.
Make this mistake visibleHelpful?