Subtract 21/40 from 81/7
1st number: 11 4/7, 2nd number: 21/40
81/7 - 21/40 is 3093/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
81/7 = 81 × 40/7 × 40 = 3240/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Subtract the two like fractions:
3240/280 - 147/280 = 3240 - 147/280 = 3093/280 - In mixed form: 1113/280
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