Subtract 63/12 from 80/21
1st number: 3 17/21, 2nd number: 5 3/12
80/21 - 63/12 is -121/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
63/12 = 63 × 7/12 × 7 = 441/84 - Subtract the two like fractions:
320/84 - 441/84 = 320 - 441/84 = -121/84
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