Subtract 7/21 from 4/5
4/5 - 7/21 is 7/15.
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,
4/5 = 4 × 21/5 × 21 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Subtract the two like fractions:
84/105 - 35/105 = 84 - 35/105 = 49/105 - After reducing the fraction, the answer is 7/15
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