Subtract 30/81 from 21/8
1st number: 2 5/8, 2nd number: 30/81
21/8 - 30/81 is 487/216.
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,
30/81 = 30 × 8/81 × 8 = 240/648 - Subtract the two like fractions:
1701/648 - 240/648 = 1701 - 240/648 = 1461/648 - After reducing the fraction, the answer is 487/216
- In mixed form: 255/216
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