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

Subtract 10/21 from 90/10

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

90/10 - 10/21 is 179/21.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
90/10 = 90 × 21/10 × 21 = 1890/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210
Subtract the two like fractions:
1890/210 - 100/210 = 1890 - 100/210 = 1790/210
After reducing the fraction, the answer is 179/21
In mixed form: 811/21

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