Subtract 81/72 from 21/14
1st number: 1 7/14, 2nd number: 1 9/72
21/14 - 81/72 is 3/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 14 × 36 = 504,
21/14 = 21 × 36/14 × 36 = 756/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Subtract the two like fractions:
756/504 - 567/504 = 756 - 567/504 = 189/504 - After reducing the fraction, the answer is 3/8
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