Add 28/9 and 21/70, Solve 3 1/9 + 21/70 as a fraction

Add 28/9 and 21/70

1^st number: 3 1/9, 2^nd number: 21/70

28/9 + 21/70 is 307/90.

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,
28/9 = 28 × 70/9 × 70 = 1960/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630
Add the two like fractions:
1960/630 + 189/630 = 1960 + 189/630 = 2149/630
2149/630 simplified gives 307/90
So, 28/9 + 21/70 = 307/90
In mixed form: 337/90

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