Add 80/12 and 30/70, Solve 6 8/12 + 30/70 as a fraction

Add 80/12 and 30/70

1^st number: 6 8/12, 2^nd number: 30/70

80/12 + 30/70 is 149/21.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 12 × 35 = 420,
80/12 = 80 × 35/12 × 35 = 2800/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
30/70 = 30 × 6/70 × 6 = 180/420
Add the two like fractions:
2800/420 + 180/420 = 2800 + 180/420 = 2980/420
2980/420 simplified gives 149/21
So, 80/12 + 30/70 = 149/21
In mixed form: 72/21

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