Subtract 45/21 from 25/2, Solve 12 1/2

Subtract 45/21 from 25/2

1^st number: 12 1/2, 2^nd number: 2 3/21

25/2 - 45/21 is 145/14.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 2 × 21 = 42,
25/2 = 25 × 21/2 × 21 = 525/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
45/21 = 45 × 2/21 × 2 = 90/42
Subtract the two like fractions:
525/42 - 90/42 = 525 - 90/42 = 435/42
After reducing the fraction, the answer is 145/14
In mixed form: 105/14

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