Subtract 1/21 from 18/12, Solve 1 6/12

Subtract 1/21 from 18/12

1^st number: 1 6/12, 2^nd number: 1/21

18/12 - 1/21 is 61/42.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
18/12 = 18 × 7/12 × 7 = 126/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
1/21 = 1 × 4/21 × 4 = 4/84
Subtract the two like fractions:
126/84 - 4/84 = 126 - 4/84 = 122/84
After reducing the fraction, the answer is 61/42
In mixed form: 119/42

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