Subtract 12/24 from 21/45
21/45 - 12/24 is -1/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 24 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 24 × 15 = 360,
12/24 = 12 × 15/24 × 15 = 180/360 - Subtract the two like fractions:
168/360 - 180/360 = 168 - 180/360 = -12/360 - After reducing the fraction, the answer is -1/30
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