Subtract 15/27 from 21/45
21/45 - 15/27 is -4/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 27 is 135
Next, find the equivalent fraction of both fractional numbers with denominator 135 - For the 1st fraction, since 45 × 3 = 135,
21/45 = 21 × 3/45 × 3 = 63/135 - Likewise, for the 2nd fraction, since 27 × 5 = 135,
15/27 = 15 × 5/27 × 5 = 75/135 - Subtract the two like fractions:
63/135 - 75/135 = 63 - 75/135 = -12/135 - After reducing the fraction, the answer is -4/45
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