Subtract 28/18 from 28/21
1st number: 1 7/21, 2nd number: 1 10/18
28/21 - 28/18 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,
28/18 = 28 × 7/18 × 7 = 196/126 - Subtract the two like fractions:
168/126 - 196/126 = 168 - 196/126 = -28/126 - After reducing the fraction, the answer is -2/9
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