Subtract 81/10 from 1/21
1st number: 1/21, 2nd number: 8 1/10
1/21 - 81/10 is -1691/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
1/21 = 1 × 10/21 × 10 = 10/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
81/10 = 81 × 21/10 × 21 = 1701/210 - Subtract the two like fractions:
10/210 - 1701/210 = 10 - 1701/210 = -1691/210
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