Subtract 21/10 from 81/7
1st number: 11 4/7, 2nd number: 2 1/10
81/7 - 21/10 is 663/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 10 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 7 × 10 = 70,
81/7 = 81 × 10/7 × 10 = 810/70 - Likewise, for the 2nd fraction, since 10 × 7 = 70,
21/10 = 21 × 7/10 × 7 = 147/70 - Subtract the two like fractions:
810/70 - 147/70 = 810 - 147/70 = 663/70 - In mixed form: 933/70
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