Add 80/21 and 14/30, Solve 3 17/21 + 14/30 as a fraction

Add 80/21 and 14/30

1^st number: 3 17/21, 2^nd number: 14/30

80/21 + 14/30 is 449/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
80/21 = 80 × 10/21 × 10 = 800/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
14/30 = 14 × 7/30 × 7 = 98/210
Add the two like fractions:
800/210 + 98/210 = 800 + 98/210 = 898/210
898/210 simplified gives 449/105
So, 80/21 + 14/30 = 449/105
In mixed form: 429/105

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