Subtract 1/21 from 70/81
70/81 - 1/21 is 463/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
70/81 = 70 × 7/81 × 7 = 490/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
1/21 = 1 × 27/21 × 27 = 27/567 - Subtract the two like fractions:
490/567 - 27/567 = 490 - 27/567 = 463/567
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