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Subtract 18/21 from 45/20

1st number: 2 5/20, 2nd number: 18/21

45/20 - 18/21 is 39/28.

Steps for subtracting fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 20 and 21 is 420

    Next, find the equivalent fraction of both fractional numbers with denominator 420
  2. For the 1st fraction, since 20 × 21 = 420,
    45/20 = 45 × 21/20 × 21 = 945/420
  3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
    18/21 = 18 × 20/21 × 20 = 360/420
  4. Subtract the two like fractions:
    945/420 - 360/420 = 945 - 360/420 = 585/420
  5. After reducing the fraction, the answer is 39/28
  6. In mixed form: 111/28

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