Subtract 28/40 from 4/7
4/7 - 28/40 is -9/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
4/7 = 4 × 40/7 × 40 = 160/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
28/40 = 28 × 7/40 × 7 = 196/280 - Subtract the two like fractions:
160/280 - 196/280 = 160 - 196/280 = -36/280 - After reducing the fraction, the answer is -9/70
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