Subtract 81/72 from 21/2
1st number: 10 1/2, 2nd number: 1 9/72
21/2 - 81/72 is 75/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 2 × 36 = 72,
21/2 = 21 × 36/2 × 36 = 756/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
81/72 = 81 × 1/72 × 1 = 81/72 - Subtract the two like fractions:
756/72 - 81/72 = 756 - 81/72 = 675/72 - After reducing the fraction, the answer is 75/8
- In mixed form: 93/8
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