Subtract 8/18 from 63/42, Solve 1 21/42

Subtract 8/18 from 63/42

1^st number: 1 21/42, 2^nd number: 8/18

63/42 - 8/18 is 19/18.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
63/42 = 63 × 3/42 × 3 = 189/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126
Subtract the two like fractions:
189/126 - 56/126 = 189 - 56/126 = 133/126
After reducing the fraction, the answer is 19/18
In mixed form: 11/18

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