Subtract 21/45 from 4/9
4/9 - 21/45 is -1/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 45 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 9 × 5 = 45,
4/9 = 4 × 5/9 × 5 = 20/45 - Likewise, for the 2nd fraction, since 45 × 1 = 45,
21/45 = 21 × 1/45 × 1 = 21/45 - Subtract the two like fractions:
20/45 - 21/45 = 20 - 21/45 = -1/45
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