Subtract 7/16 from 81/21, Solve 3 18/21

Subtract 7/16 from 81/21

1^st number: 3 18/21, 2^nd number: 7/16

81/21 - 7/16 is 383/112.

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

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 21 × 16 = 336,
81/21 = 81 × 16/21 × 16 = 1296/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
7/16 = 7 × 21/16 × 21 = 147/336
Subtract the two like fractions:
1296/336 - 147/336 = 1296 - 147/336 = 1149/336
After reducing the fraction, the answer is 383/112
In mixed form: 347/112

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