Subtract 1/42 from 21/9, Solve 2 3/9

Subtract 1/42 from 21/9

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

21/9 - 1/42 is 97/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 9 × 14 = 126,
21/9 = 21 × 14/9 × 14 = 294/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
1/42 = 1 × 3/42 × 3 = 3/126
Subtract the two like fractions:
294/126 - 3/126 = 294 - 3/126 = 291/126
After reducing the fraction, the answer is 97/42
In mixed form: 213/42

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