Subtract 1/7 from 4/21
4/21 - 1/7 is 1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
4/21 = 4 × 1/21 × 1 = 4/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
1/7 = 1 × 3/7 × 3 = 3/21 - Subtract the two like fractions:
4/21 - 3/21 = 4 - 3/21 = 1/21
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