Subtract 20/21 from 28/35
28/35 - 20/21 is -16/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
28/35 = 28 × 3/35 × 3 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Subtract the two like fractions:
84/105 - 100/105 = 84 - 100/105 = -16/105
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