Subtract 45/21 from 30/2, Solve 15 0/2

Subtract 45/21 from 30/2

1^st number: 15 0/2, 2^nd number: 2 3/21

30/2 - 45/21 is 90/7.

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,
30/2 = 30 × 21/2 × 21 = 630/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
45/21 = 45 × 2/21 × 2 = 90/42
Subtract the two like fractions:
630/42 - 90/42 = 630 - 90/42 = 540/42
After reducing the fraction, the answer is 90/7
In mixed form: 126/7

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