Subtract 1/21 from 45/81
45/81 - 1/21 is 32/63.
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,
45/81 = 45 × 7/81 × 7 = 315/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
1/21 = 1 × 27/21 × 27 = 27/567 - Subtract the two like fractions:
315/567 - 27/567 = 315 - 27/567 = 288/567 - After reducing the fraction, the answer is 32/63
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