Subtract 81/10 from 10/21
1st number: 10/21, 2nd number: 8 1/10
10/21 - 81/10 is -1601/210.
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,
10/21 = 10 × 10/21 × 10 = 100/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
81/10 = 81 × 21/10 × 21 = 1701/210 - Subtract the two like fractions:
100/210 - 1701/210 = 100 - 1701/210 = -1601/210
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