Subtract 72/20 from 12/21
1st number: 12/21, 2nd number: 3 12/20
12/21 - 72/20 is -106/35.
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,
12/21 = 12 × 20/21 × 20 = 240/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Subtract the two like fractions:
240/420 - 1512/420 = 240 - 1512/420 = -1272/420 - After reducing the fraction, the answer is -106/35
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