Subtract 7/21 from 63/2, Solve 31 1/2

Subtract 7/21 from 63/2

1^st number: 31 1/2, 2^nd number: 7/21

63/2 - 7/21 is 187/6.

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,
63/2 = 63 × 21/2 × 21 = 1323/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
7/21 = 7 × 2/21 × 2 = 14/42
Subtract the two like fractions:
1323/42 - 14/42 = 1323 - 14/42 = 1309/42
After reducing the fraction, the answer is 187/6
In mixed form: 311/6

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