Subtract 15/42 from 5/2, Solve 2 1/2

Subtract 15/42 from 5/2

1^st number: 2 1/2, 2^nd number: 15/42

5/2 - 15/42 is 15/7.

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,
5/2 = 5 × 21/2 × 21 = 105/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
15/42 = 15 × 1/42 × 1 = 15/42
Subtract the two like fractions:
105/42 - 15/42 = 105 - 15/42 = 90/42
After reducing the fraction, the answer is 15/7
In mixed form: 21/7

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