Subtract 42/81 from 15/35
15/35 - 42/81 is -17/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 81 is 2835
Next, find the equivalent fraction of both fractional numbers with denominator 2835 - For the 1st fraction, since 35 × 81 = 2835,
15/35 = 15 × 81/35 × 81 = 1215/2835 - Likewise, for the 2nd fraction, since 81 × 35 = 2835,
42/81 = 42 × 35/81 × 35 = 1470/2835 - Subtract the two like fractions:
1215/2835 - 1470/2835 = 1215 - 1470/2835 = -255/2835 - After reducing the fraction, the answer is -17/189
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