Subtract 28/7 from 21/40
1st number: 21/40, 2nd number: 4 0/7
21/40 - 28/7 is -139/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 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 7 × 40 = 280,
28/7 = 28 × 40/7 × 40 = 1120/280 - Subtract the two like fractions:
147/280 - 1120/280 = 147 - 1120/280 = -973/280 - After reducing the fraction, the answer is -139/40
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