Subtract 10/21 from 81/8
1st number: 10 1/8, 2nd number: 10/21
81/8 - 10/21 is 1621/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
81/8 = 81 × 21/8 × 21 = 1701/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
10/21 = 10 × 8/21 × 8 = 80/168 - Subtract the two like fractions:
1701/168 - 80/168 = 1701 - 80/168 = 1621/168 - In mixed form: 9109/168
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