Subtract 30/18 from 28/21
1st number: 1 7/21, 2nd number: 1 12/18
28/21 - 30/18 is -1/3.
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,
30/18 = 30 × 7/18 × 7 = 210/126 - Subtract the two like fractions:
168/126 - 210/126 = 168 - 210/126 = -42/126 - After reducing the fraction, the answer is -1/3
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