Subtract 81/15 from 63/21
1st number: 3 0/21, 2nd number: 5 6/15
63/21 - 81/15 is -12/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
63/21 = 63 × 5/21 × 5 = 315/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
81/15 = 81 × 7/15 × 7 = 567/105 - Subtract the two like fractions:
315/105 - 567/105 = 315 - 567/105 = -252/105 - After reducing the fraction, the answer is -12/5
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