Subtract 28/4 from 20/21
1st number: 20/21, 2nd number: 7 0/4
20/21 - 28/4 is -127/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
28/4 = 28 × 21/4 × 21 = 588/84 - Subtract the two like fractions:
80/84 - 588/84 = 80 - 588/84 = -508/84 - After reducing the fraction, the answer is -127/21
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