Subtract 81/21 from 54/15
1st number: 3 9/15, 2nd number: 3 18/21
54/15 - 81/21 is -9/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
54/15 = 54 × 7/15 × 7 = 378/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Subtract the two like fractions:
378/105 - 405/105 = 378 - 405/105 = -27/105 - After reducing the fraction, the answer is -9/35
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