Subtract 28/5 from 20/21
1st number: 20/21, 2nd number: 5 3/5
20/21 - 28/5 is -488/105.
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,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
28/5 = 28 × 21/5 × 21 = 588/105 - Subtract the two like fractions:
100/105 - 588/105 = 100 - 588/105 = -488/105
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