Subtract 21/8 from 81/70
1st number: 1 11/70, 2nd number: 2 5/8
81/70 - 21/8 is -411/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 8 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
81/70 = 81 × 4/70 × 4 = 324/280 - Likewise, for the 2nd fraction, since 8 × 35 = 280,
21/8 = 21 × 35/8 × 35 = 735/280 - Subtract the two like fractions:
324/280 - 735/280 = 324 - 735/280 = -411/280
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