Subtract 5/21 from 20/16, Solve 1 4/16

Subtract 5/21 from 20/16

1^st number: 1 4/16, 2^nd number: 5/21

20/16 - 5/21 is 85/84.

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,
20/16 = 20 × 21/16 × 21 = 420/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
5/21 = 5 × 16/21 × 16 = 80/336
Subtract the two like fractions:
420/336 - 80/336 = 420 - 80/336 = 340/336
After reducing the fraction, the answer is 85/84
In mixed form: 11/84

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