Subtract 21/10 from 81/8
1st number: 10 1/8, 2nd number: 2 1/10
81/8 - 21/10 is 321/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 10 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
81/8 = 81 × 5/8 × 5 = 405/40 - Likewise, for the 2nd fraction, since 10 × 4 = 40,
21/10 = 21 × 4/10 × 4 = 84/40 - Subtract the two like fractions:
405/40 - 84/40 = 405 - 84/40 = 321/40 - In mixed form: 81/40
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