Subtract 30/40 from 18/28
18/28 - 30/40 is -3/28.
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,
18/28 = 18 × 10/28 × 10 = 180/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Subtract the two like fractions:
180/280 - 210/280 = 180 - 210/280 = -30/280 - After reducing the fraction, the answer is -3/28
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