Add 3/21 and 84/10, Solve 3/21 + 8 4/10 as a fraction

Add 3/21 and 84/10

1^st number: 3/21, 2^nd number: 8 4/10

3/21 + 84/10 is 299/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
3/21 = 3 × 10/21 × 10 = 30/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
84/10 = 84 × 21/10 × 21 = 1764/210
Add the two like fractions:
30/210 + 1764/210 = 30 + 1764/210 = 1794/210
1794/210 simplified gives 299/35
So, 3/21 + 84/10 = 299/35
In mixed form: 819/35

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