Subtract 2/27 from 28/21, Solve 1 7/21

Subtract 2/27 from 28/21

1^st number: 1 7/21, 2^nd number: 2/27

28/21 - 2/27 is 34/27.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
28/21 = 28 × 9/21 × 9 = 252/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
2/27 = 2 × 7/27 × 7 = 14/189
Subtract the two like fractions:
252/189 - 14/189 = 252 - 14/189 = 238/189
After reducing the fraction, the answer is 34/27
In mixed form: 17/27

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