Subtract 80/81 from 21/8
1st number: 2 5/8, 2nd number: 80/81
21/8 - 80/81 is 1061/648.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 8 × 81 = 648,
21/8 = 21 × 81/8 × 81 = 1701/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
80/81 = 80 × 8/81 × 8 = 640/648 - Subtract the two like fractions:
1701/648 - 640/648 = 1701 - 640/648 = 1061/648 - In mixed form: 1413/648
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