Subtract 27/21 from 63/4, Solve 15 3/4

Subtract 27/21 from 63/4

1^st number: 15 3/4, 2^nd number: 1 6/21

63/4 - 27/21 is 405/28.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
63/4 = 63 × 21/4 × 21 = 1323/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
27/21 = 27 × 4/21 × 4 = 108/84
Subtract the two like fractions:
1323/84 - 108/84 = 1323 - 108/84 = 1215/84
After reducing the fraction, the answer is 405/28
In mixed form: 1413/28

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