Subtract 21/45 from 10/81
10/81 - 21/45 is -139/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
10/81 = 10 × 5/81 × 5 = 50/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
21/45 = 21 × 9/45 × 9 = 189/405 - Subtract the two like fractions:
50/405 - 189/405 = 50 - 189/405 = -139/405
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