the best puzzle

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Across
  1. 4. a fraction is in simplest form when the numerator and the denominator have only one as a common factor
  2. 6. a reciprocal of a number that is multiplied by that number resulting in a product of 1
  3. 7. a common multiple of 2 of more denominators
  4. 8. numbers that are easy to compute mentally
Down
  1. 1. fractions that name the same amount of a part
  2. 2. a number that is made up of a whole number and a fraction
  3. 3. two number that are reciprocals of each other if their products equal 1
  4. 5. a number names a part of a whole or a part of a group