Subtract 72/20 from 63/21
1st number: 3 0/21, 2nd number: 3 12/20
63/21 - 72/20 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
63/21 = 63 × 20/21 × 20 = 1260/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Subtract the two like fractions:
1260/420 - 1512/420 = 1260 - 1512/420 = -252/420 - After reducing the fraction, the answer is -3/5
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