Subtract 21/70 from 20/9, Solve 2 2/9

Subtract 21/70 from 20/9

1^st number: 2 2/9, 2^nd number: 21/70

20/9 - 21/70 is 173/90.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 9 × 70 = 630,
20/9 = 20 × 70/9 × 70 = 1400/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630
Subtract the two like fractions:
1400/630 - 189/630 = 1400 - 189/630 = 1211/630
After reducing the fraction, the answer is 173/90
In mixed form: 183/90

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