Subtract 5/21 from 1/5
1/5 - 5/21 is -4/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
1/5 = 1 × 21/5 × 21 = 21/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
5/21 = 5 × 5/21 × 5 = 25/105 - Subtract the two like fractions:
21/105 - 25/105 = 21 - 25/105 = -4/105
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