Subtract 28/21 from 9/84
1st number: 9/84, 2nd number: 1 7/21
9/84 - 28/21 is -103/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
9/84 = 9 × 1/84 × 1 = 9/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Subtract the two like fractions:
9/84 - 112/84 = 9 - 112/84 = -103/84
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