Subtract 20/18 from 28/21
1st number: 1 7/21, 2nd number: 1 2/18
28/21 - 20/18 is 2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
28/21 = 28 × 6/21 × 6 = 168/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126 - Subtract the two like fractions:
168/126 - 140/126 = 168 - 140/126 = 28/126 - After reducing the fraction, the answer is 2/9
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