Subtract 9/15 from 21/27
21/27 - 9/15 is 8/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 15 is 135
Next, find the equivalent fraction of both fractional numbers with denominator 135 - For the 1st fraction, since 27 × 5 = 135,
21/27 = 21 × 5/27 × 5 = 105/135 - Likewise, for the 2nd fraction, since 15 × 9 = 135,
9/15 = 9 × 9/15 × 9 = 81/135 - Subtract the two like fractions:
105/135 - 81/135 = 105 - 81/135 = 24/135 - After reducing the fraction, the answer is 8/45
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