Subtract 49/20 from 28/81
1st number: 28/81, 2nd number: 2 9/20
28/81 - 49/20 is -3409/1620.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
28/81 = 28 × 20/81 × 20 = 560/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
49/20 = 49 × 81/20 × 81 = 3969/1620 - Subtract the two like fractions:
560/1620 - 3969/1620 = 560 - 3969/1620 = -3409/1620
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