Subtract 8/80 from 75/21, Solve 3 12/21

Subtract 8/80 from 75/21

1^st number: 3 12/21, 2^nd number: 8/80

75/21 - 8/80 is 243/70.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
75/21 = 75 × 80/21 × 80 = 6000/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
8/80 = 8 × 21/80 × 21 = 168/1680
Subtract the two like fractions:
6000/1680 - 168/1680 = 6000 - 168/1680 = 5832/1680
After reducing the fraction, the answer is 243/70
In mixed form: 333/70

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