Subtract 30/27 from 50/21, Solve 2 8/21

Subtract 30/27 from 50/21

1^st number: 2 8/21, 2^nd number: 1 3/27

50/21 - 30/27 is 80/63.

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,
50/21 = 50 × 9/21 × 9 = 450/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
30/27 = 30 × 7/27 × 7 = 210/189
Subtract the two like fractions:
450/189 - 210/189 = 450 - 210/189 = 240/189
After reducing the fraction, the answer is 80/63
In mixed form: 117/63

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