Subtract 5/81 from 21/20
1st number: 1 1/20, 2nd number: 5/81
21/20 - 5/81 is 1601/1620.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
21/20 = 21 × 81/20 × 81 = 1701/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
5/81 = 5 × 20/81 × 20 = 100/1620 - Subtract the two like fractions:
1701/1620 - 100/1620 = 1701 - 100/1620 = 1601/1620
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