Subtract 21/42 from 84/2, Solve 42 0/2

Subtract 21/42 from 84/2

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

84/2 - 21/42 is 83/2.

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,
84/2 = 84 × 21/2 × 21 = 1764/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42
Subtract the two like fractions:
1764/42 - 21/42 = 1764 - 21/42 = 1743/42
After reducing the fraction, the answer is 83/2
In mixed form: 411/2

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