Subtract 21/5 from 28/21
1st number: 1 7/21, 2nd number: 4 1/5
28/21 - 21/5 is -43/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
21/5 = 21 × 21/5 × 21 = 441/105 - Subtract the two like fractions:
140/105 - 441/105 = 140 - 441/105 = -301/105 - After reducing the fraction, the answer is -43/15
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