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Subtract 21/18 from 7/20

1st number: 7/20, 2nd number: 1 3/18

7/20 - 21/18 is -49/60.

Steps for subtracting fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 20 and 18 is 180
  2. For the 1st fraction, since 20 × 9 = 180,
    7/20 = 7 × 9/20 × 9 = 63/180
  3. Likewise, for the 2nd fraction, since 18 × 10 = 180,
    21/18 = 21 × 10/18 × 10 = 210/180
  4. Subtract the two fractions:
    63/180 - 210/180 = 63 - 210/180 = -147/180
  5. After reducing the fraction, the answer is -49/60

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