Subtract 20/30 from 28/45
28/45 - 20/30 is -2/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
28/45 = 28 × 2/45 × 2 = 56/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
20/30 = 20 × 3/30 × 3 = 60/90 - Subtract the two like fractions:
56/90 - 60/90 = 56 - 60/90 = -4/90 - After reducing the fraction, the answer is -2/45
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