Subtract 80/21 from 30/27, Solve 1 3/27

Subtract 80/21 from 30/27

1^st number: 1 3/27, 2^nd number: 3 17/21

30/27 - 80/21 is -170/63.

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

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 27 × 7 = 189,
30/27 = 30 × 7/27 × 7 = 210/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
80/21 = 80 × 9/21 × 9 = 720/189
Subtract the two like fractions:
210/189 - 720/189 = 210 - 720/189 = -510/189
After reducing the fraction, the answer is -170/63

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