Subtract 81/21 from 63/20
1st number: 3 3/20, 2nd number: 3 18/21
63/20 - 81/21 is -99/140.
Steps for subtracting fractions
- 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 - For the 1st fraction, since 20 × 21 = 420,
63/20 = 63 × 21/20 × 21 = 1323/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
81/21 = 81 × 20/21 × 20 = 1620/420 - Subtract the two like fractions:
1323/420 - 1620/420 = 1323 - 1620/420 = -297/420 - After reducing the fraction, the answer is -99/140
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