Subtract 28/40 from 20/30
20/30 - 28/40 is -1/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
20/30 = 20 × 4/30 × 4 = 80/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
28/40 = 28 × 3/40 × 3 = 84/120 - Subtract the two like fractions:
80/120 - 84/120 = 80 - 84/120 = -4/120 - After reducing the fraction, the answer is -1/30
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