Subtract 12/15 from 21/45
21/45 - 12/15 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 15 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 15 × 3 = 45,
12/15 = 12 × 3/15 × 3 = 36/45 - Subtract the two like fractions:
21/45 - 36/45 = 21 - 36/45 = -15/45 - After reducing the fraction, the answer is -1/3
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