Subtract 1/28 from 21/12
1st number: 1 9/12, 2nd number: 1/28
21/12 - 1/28 is 12/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
1/28 = 1 × 3/28 × 3 = 3/84 - Subtract the two like fractions:
147/84 - 3/84 = 147 - 3/84 = 144/84 - After reducing the fraction, the answer is 12/7
- In mixed form: 15/7
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