Subtract 21/28 from 15/12
1st number: 1 3/12, 2nd number: 21/28
15/12 - 21/28 is 1/2.
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,
15/12 = 15 × 7/12 × 7 = 105/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Subtract the two like fractions:
105/84 - 63/84 = 105 - 63/84 = 42/84 - After reducing the fraction, the answer is 1/2
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