Subtract 18/81 from 21/35
21/35 - 18/81 is 17/45.
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,
21/35 = 21 × 81/35 × 81 = 1701/2835 - Likewise, for the 2nd fraction, since 81 × 35 = 2835,
18/81 = 18 × 35/81 × 35 = 630/2835 - Subtract the two like fractions:
1701/2835 - 630/2835 = 1701 - 630/2835 = 1071/2835 - After reducing the fraction, the answer is 17/45
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