Subtract 35/21 from 20/80, Solve 20/80

Subtract 35/21 from 20/80

1^st number: 20/80, 2^nd number: 1 14/21

20/80 - 35/21 is -17/12.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
35/21 = 35 × 80/21 × 80 = 2800/1680
Subtract the two like fractions:
420/1680 - 2800/1680 = 420 - 2800/1680 = -2380/1680
After reducing the fraction, the answer is -17/12

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