Subtract 21/40 from 3/28
3/28 - 21/40 is -117/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 28 × 10 = 280,
3/28 = 3 × 10/28 × 10 = 30/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Subtract the two like fractions:
30/280 - 147/280 = 30 - 147/280 = -117/280
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