Subtract 42/81 from 1/49, Solve 1/49

Subtract 42/81 from 1/49

1/49 - 42/81 is -659/1323.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 81 is 3969

Next, find the equivalent fraction of both fractional numbers with denominator 3969
For the 1st fraction, since 49 × 81 = 3969,
1/49 = 1 × 81/49 × 81 = 81/3969
Likewise, for the 2nd fraction, since 81 × 49 = 3969,
42/81 = 42 × 49/81 × 49 = 2058/3969
Subtract the two like fractions:
81/3969 - 2058/3969 = 81 - 2058/3969 = -1977/3969
After reducing the fraction, the answer is -659/1323

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