Add 30/21 and 80/5, Solve 1 9/21 + 16 0/5 as a fraction

Add 30/21 and 80/5

1^st number: 1 9/21, 2^nd number: 16 0/5

30/21 + 80/5 is 122/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
30/21 = 30 × 5/21 × 5 = 150/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
80/5 = 80 × 21/5 × 21 = 1680/105
Add the two like fractions:
150/105 + 1680/105 = 150 + 1680/105 = 1830/105
1830/105 simplified gives 122/7
So, 30/21 + 80/5 = 122/7
In mixed form: 173/7

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