Subtract 21/16 from 70/21, Solve 3 7/21

Subtract 21/16 from 70/21

1^st number: 3 7/21, 2^nd number: 1 5/16

70/21 - 21/16 is 97/48.

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,
70/21 = 70 × 16/21 × 16 = 1120/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
21/16 = 21 × 21/16 × 21 = 441/336
Subtract the two like fractions:
1120/336 - 441/336 = 1120 - 441/336 = 679/336
After reducing the fraction, the answer is 97/48
In mixed form: 21/48

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