Subtract 3/81 from 21/14, Solve 1 7/14

Subtract 3/81 from 21/14

1^st number: 1 7/14, 2^nd number: 3/81

21/14 - 3/81 is 79/54.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 81 is 1134

Next, find the equivalent fraction of both fractional numbers with denominator 1134
For the 1st fraction, since 14 × 81 = 1134,
21/14 = 21 × 81/14 × 81 = 1701/1134
Likewise, for the 2nd fraction, since 81 × 14 = 1134,
3/81 = 3 × 14/81 × 14 = 42/1134
Subtract the two like fractions:
1701/1134 - 42/1134 = 1701 - 42/1134 = 1659/1134
After reducing the fraction, the answer is 79/54
In mixed form: 125/54

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