Subtract 20/42 from 75/27, Solve 2 21/27

Subtract 20/42 from 75/27

1^st number: 2 21/27, 2^nd number: 20/42

75/27 - 20/42 is 145/63.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 27 × 14 = 378,
75/27 = 75 × 14/27 × 14 = 1050/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
20/42 = 20 × 9/42 × 9 = 180/378
Subtract the two like fractions:
1050/378 - 180/378 = 1050 - 180/378 = 870/378
After reducing the fraction, the answer is 145/63
In mixed form: 219/63

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