Subtract 8/54 from 30/21, Solve 1 9/21

Subtract 8/54 from 30/21

1^st number: 1 9/21, 2^nd number: 8/54

30/21 - 8/54 is 242/189.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
30/21 = 30 × 18/21 × 18 = 540/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
8/54 = 8 × 7/54 × 7 = 56/378
Subtract the two like fractions:
540/378 - 56/378 = 540 - 56/378 = 484/378
After reducing the fraction, the answer is 242/189
In mixed form: 153/189

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