Subtract 80/21 from 90/9, Solve 10 0/9

Subtract 80/21 from 90/9

1^st number: 10 0/9, 2^nd number: 3 17/21

90/9 - 80/21 is 130/21.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 9 × 7 = 63,
90/9 = 90 × 7/9 × 7 = 630/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
80/21 = 80 × 3/21 × 3 = 240/63
Subtract the two like fractions:
630/63 - 240/63 = 630 - 240/63 = 390/63
After reducing the fraction, the answer is 130/21
In mixed form: 64/21

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