Subtract 9/7 from 42/18, Solve 2 6/18

Subtract 9/7 from 42/18

1^st number: 2 6/18, 2^nd number: 1 2/7

42/18 - 9/7 is 22/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 7 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
9/7 = 9 × 18/7 × 18 = 162/126
Subtract the two like fractions:
294/126 - 162/126 = 294 - 162/126 = 132/126
After reducing the fraction, the answer is 22/21
In mixed form: 11/21

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