Mathematics Test—Calculator

The total number of people who recalled at least 1 dream is the sum of the 79 people in Group Y who recalled at least 1 dream, the 28 people in Group X who recalled 1 to 4 dreams, and the 57 people in Group X who recalled 5 or more dreams: 79 plus 28 plus 57, equals 164. Therefore, the probability is the fraction 79 over 164. ................
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