Subtract 7/9 from 21/45
21/45 - 7/9 is -14/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 45 × 1 = 45,
21/45 = 21 × 1/45 × 1 = 21/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
7/9 = 7 × 5/9 × 5 = 35/45 - Subtract the two like fractions:
21/45 - 35/45 = 21 - 35/45 = -14/45
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