Subtract 81/40 from 30/70
1st number: 30/70, 2nd number: 2 1/40
30/70 - 81/40 is -447/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
30/70 = 30 × 4/70 × 4 = 120/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
81/40 = 81 × 7/40 × 7 = 567/280 - Subtract the two like fractions:
120/280 - 567/280 = 120 - 567/280 = -447/280
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