Subtract 20/9 from 28/21
1st number: 1 7/21, 2nd number: 2 2/9
28/21 - 20/9 is -8/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
28/21 = 28 × 3/21 × 3 = 84/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
20/9 = 20 × 7/9 × 7 = 140/63 - Subtract the two like fractions:
84/63 - 140/63 = 84 - 140/63 = -56/63 - After reducing the fraction, the answer is -8/9
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