Add 40/21 and 28/8, Solve 1 19/21 + 3 4/8 as a fraction

Add 40/21 and 28/8

1^st number: 1 19/21, 2^nd number: 3 4/8

40/21 + 28/8 is 227/42.

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,
40/21 = 40 × 8/21 × 8 = 320/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
28/8 = 28 × 21/8 × 21 = 588/168
Add the two like fractions:
320/168 + 588/168 = 320 + 588/168 = 908/168
908/168 simplified gives 227/42
So, 40/21 + 28/8 = 227/42
In mixed form: 517/42

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