Add 64/12 and 20/42, Solve 5 4/12 + 20/42 as a fraction

Add 64/12 and 20/42

1^st number: 5 4/12, 2^nd number: 20/42

64/12 + 20/42 is 122/21.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
64/12 = 64 × 7/12 × 7 = 448/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84
Add the two like fractions:
448/84 + 40/84 = 448 + 40/84 = 488/84
488/84 simplified gives 122/21
So, 64/12 + 20/42 = 122/21
In mixed form: 517/21

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