Subtract 15/81 from 3/72
3/72 - 15/81 is -31/216.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
3/72 = 3 × 9/72 × 9 = 27/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
15/81 = 15 × 8/81 × 8 = 120/648 - Subtract the two like fractions:
27/648 - 120/648 = 27 - 120/648 = -93/648 - After reducing the fraction, the answer is -31/216
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