Subtract 63/42 from 42/2, Solve 21 0/2

Subtract 63/42 from 42/2

1^st number: 21 0/2, 2^nd number: 1 21/42

42/2 - 63/42 is 39/2.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 2 × 21 = 42,
42/2 = 42 × 21/2 × 21 = 882/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
63/42 = 63 × 1/42 × 1 = 63/42
Subtract the two like fractions:
882/42 - 63/42 = 882 - 63/42 = 819/42
After reducing the fraction, the answer is 39/2
In mixed form: 191/2

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