Subtract 9/21 from 12/45
12/45 - 9/21 is -17/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
9/21 = 9 × 15/21 × 15 = 135/315 - Subtract the two like fractions:
84/315 - 135/315 = 84 - 135/315 = -51/315 - After reducing the fraction, the answer is -17/105
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