Subtract 81/70 from 28/40
1st number: 28/40, 2nd number: 1 11/70
28/40 - 81/70 is -16/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
28/40 = 28 × 7/40 × 7 = 196/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
81/70 = 81 × 4/70 × 4 = 324/280 - Subtract the two like fractions:
196/280 - 324/280 = 196 - 324/280 = -128/280 - After reducing the fraction, the answer is -16/35
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