Subtract 9/49 from 21/81
21/81 - 9/49 is 100/1323.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 49 is 3969
Next, find the equivalent fraction of both fractional numbers with denominator 3969 - For the 1st fraction, since 81 × 49 = 3969,
21/81 = 21 × 49/81 × 49 = 1029/3969 - Likewise, for the 2nd fraction, since 49 × 81 = 3969,
9/49 = 9 × 81/49 × 81 = 729/3969 - Subtract the two like fractions:
1029/3969 - 729/3969 = 1029 - 729/3969 = 300/3969 - After reducing the fraction, the answer is 100/1323
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