Subtract 5/21 from 42/27, Solve 1 15/27

Subtract 5/21 from 42/27

1^st number: 1 15/27, 2^nd number: 5/21

42/27 - 5/21 is 83/63.

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,
42/27 = 42 × 7/27 × 7 = 294/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
5/21 = 5 × 9/21 × 9 = 45/189
Subtract the two like fractions:
294/189 - 45/189 = 294 - 45/189 = 249/189
After reducing the fraction, the answer is 83/63
In mixed form: 120/63

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