Add 80/12 and 21/42, Solve 6 8/12 + 21/42 as a fraction

Add 80/12 and 21/42

1^st number: 6 8/12, 2^nd number: 21/42

80/12 + 21/42 is 43/6.

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,
80/12 = 80 × 7/12 × 7 = 560/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84
Add the two like fractions:
560/84 + 42/84 = 560 + 42/84 = 602/84
602/84 simplified gives 43/6
So, 80/12 + 21/42 = 43/6
In mixed form: 71/6

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