Subtract 54/12 from 42/2, Solve 21 0/2

Subtract 54/12 from 42/2

1^st number: 21 0/2, 2^nd number: 4 6/12

42/2 - 54/12 is 33/2.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 12 is 12

Next, find the equivalent fraction of both fractional numbers with denominator 12
For the 1st fraction, since 2 × 6 = 12,
42/2 = 42 × 6/2 × 6 = 252/12
Likewise, for the 2nd fraction, since 12 × 1 = 12,
54/12 = 54 × 1/12 × 1 = 54/12
Subtract the two like fractions:
252/12 - 54/12 = 252 - 54/12 = 198/12
After reducing the fraction, the answer is 33/2
In mixed form: 161/2

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