Subtract 30/28 from 21/40
1st number: 21/40, 2nd number: 1 2/28
21/40 - 30/28 is -153/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 28 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Likewise, for the 2nd fraction, since 28 × 10 = 280,
30/28 = 30 × 10/28 × 10 = 300/280 - Subtract the two like fractions:
147/280 - 300/280 = 147 - 300/280 = -153/280
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