Subtract 70/21 from 20/16, Solve 1 4/16

Subtract 70/21 from 20/16

1^st number: 1 4/16, 2^nd number: 3 7/21

20/16 - 70/21 is -25/12.

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,
70/21 = 70 × 16/21 × 16 = 1120/336
Subtract the two like fractions:
420/336 - 1120/336 = 420 - 1120/336 = -700/336
After reducing the fraction, the answer is -25/12

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