Subtract 21/35 from 21/81
21/81 - 21/35 is -46/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 35 is 2835
Next, find the equivalent fraction of both fractional numbers with denominator 2835 - For the 1st fraction, since 81 × 35 = 2835,
21/81 = 21 × 35/81 × 35 = 735/2835 - Likewise, for the 2nd fraction, since 35 × 81 = 2835,
21/35 = 21 × 81/35 × 81 = 1701/2835 - Subtract the two like fractions:
735/2835 - 1701/2835 = 735 - 1701/2835 = -966/2835 - After reducing the fraction, the answer is -46/135
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