Subtract 81/21 from 28/2, Solve 14 0/2

Subtract 81/21 from 28/2

1^st number: 14 0/2, 2^nd number: 3 18/21

28/2 - 81/21 is 71/7.

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,
28/2 = 28 × 21/2 × 21 = 588/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42
Subtract the two like fractions:
588/42 - 162/42 = 588 - 162/42 = 426/42
After reducing the fraction, the answer is 71/7
In mixed form: 101/7

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