Subtract 30/27 from 70/21, Solve 3 7/21

Subtract 30/27 from 70/21

1^st number: 3 7/21, 2^nd number: 1 3/27

70/21 - 30/27 is 20/9.

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,
70/21 = 70 × 9/21 × 9 = 630/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
30/27 = 30 × 7/27 × 7 = 210/189
Subtract the two like fractions:
630/189 - 210/189 = 630 - 210/189 = 420/189
After reducing the fraction, the answer is 20/9
In mixed form: 22/9

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