Subtract 12/80 from 42/2, Solve 21 0/2

Subtract 12/80 from 42/2

1^st number: 21 0/2, 2^nd number: 12/80

42/2 - 12/80 is 417/20.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 2 × 40 = 80,
42/2 = 42 × 40/2 × 40 = 1680/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
12/80 = 12 × 1/80 × 1 = 12/80
Subtract the two like fractions:
1680/80 - 12/80 = 1680 - 12/80 = 1668/80
After reducing the fraction, the answer is 417/20
In mixed form: 2017/20

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