Subtract 21/12 from 45/28
1st number: 1 17/28, 2nd number: 1 9/12
45/28 - 21/12 is -1/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
45/28 = 45 × 3/28 × 3 = 135/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Subtract the two like fractions:
135/84 - 147/84 = 135 - 147/84 = -12/84 - After reducing the fraction, the answer is -1/7
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