Subtract 21/9 from 84/42, Solve 2 0/42

Subtract 21/9 from 84/42

1^st number: 2 0/42, 2^nd number: 2 3/9

84/42 - 21/9 is -1/3.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
84/42 = 84 × 3/42 × 3 = 252/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
21/9 = 21 × 14/9 × 14 = 294/126
Subtract the two like fractions:
252/126 - 294/126 = 252 - 294/126 = -42/126
After reducing the fraction, the answer is -1/3

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