Add 21/70 and 84/9, Solve 21/70 + 9 3/9 as a fraction

Add 21/70 and 84/9

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

21/70 + 84/9 is 289/30.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630
Likewise, for the 2nd fraction, since 9 × 70 = 630,
84/9 = 84 × 70/9 × 70 = 5880/630
Add the two like fractions:
189/630 + 5880/630 = 189 + 5880/630 = 6069/630
6069/630 simplified gives 289/30
So, 21/70 + 84/9 = 289/30
In mixed form: 919/30

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