Subtract 8/72 from 81/21
1st number: 3 18/21, 2nd number: 8/72
81/21 - 8/72 is 236/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
81/21 = 81 × 24/21 × 24 = 1944/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
8/72 = 8 × 7/72 × 7 = 56/504 - Subtract the two like fractions:
1944/504 - 56/504 = 1944 - 56/504 = 1888/504 - After reducing the fraction, the answer is 236/63
- In mixed form: 347/63
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