Subtract 9/81 from 21/14, Solve 1 7/14

Subtract 9/81 from 21/14

1^st number: 1 7/14, 2^nd number: 9/81

21/14 - 9/81 is 25/18.

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,
9/81 = 9 × 14/81 × 14 = 126/1134
Subtract the two like fractions:
1701/1134 - 126/1134 = 1701 - 126/1134 = 1575/1134
After reducing the fraction, the answer is 25/18
In mixed form: 17/18

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