Subtract 54/21 from 81/16, Solve 5 1/16

Subtract 54/21 from 81/16

1^st number: 5 1/16, 2^nd number: 2 12/21

81/16 - 54/21 is 279/112.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 21 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 16 × 21 = 336,
81/16 = 81 × 21/16 × 21 = 1701/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
54/21 = 54 × 16/21 × 16 = 864/336
Subtract the two like fractions:
1701/336 - 864/336 = 1701 - 864/336 = 837/336
After reducing the fraction, the answer is 279/112
In mixed form: 255/112

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