Subtract 21/7 from 21/28
1st number: 21/28, 2nd number: 3 0/7
21/28 - 21/7 is -9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 7 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 28 × 1 = 28,
21/28 = 21 × 1/28 × 1 = 21/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
21/7 = 21 × 4/7 × 4 = 84/28 - Subtract the two like fractions:
21/28 - 84/28 = 21 - 84/28 = -63/28 - After reducing the fraction, the answer is -9/4
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