Add 30/21 and 28/8, Solve 1 9/21 + 3 4/8 as a fraction

Add 30/21 and 28/8

1^st number: 1 9/21, 2^nd number: 3 4/8

30/21 + 28/8 is 69/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
30/21 = 30 × 8/21 × 8 = 240/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
28/8 = 28 × 21/8 × 21 = 588/168
Add the two like fractions:
240/168 + 588/168 = 240 + 588/168 = 828/168
828/168 simplified gives 69/14
So, 30/21 + 28/8 = 69/14
In mixed form: 413/14

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