Add 2/15 and 80/21, Solve 2/15 + 3 17/21 as a fraction

Add 2/15 and 80/21

1^st number: 2/15, 2^nd number: 3 17/21

2/15 + 80/21 is 138/35.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
2/15 = 2 × 7/15 × 7 = 14/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105
Add the two like fractions:
14/105 + 400/105 = 14 + 400/105 = 414/105
414/105 simplified gives 138/35
So, 2/15 + 80/21 = 138/35
In mixed form: 333/35

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