Subtract 30/21 from 18/28
1st number: 18/28, 2nd number: 1 9/21
18/28 - 30/21 is -11/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84 - Subtract the two like fractions:
54/84 - 120/84 = 54 - 120/84 = -66/84 - After reducing the fraction, the answer is -11/14
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