Add 10/21 and 80/30, Solve 10/21 + 2 20/30 as a fraction

Add 10/21 and 80/30

1^st number: 10/21, 2^nd number: 2 20/30

10/21 + 80/30 is 22/7.

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,
10/21 = 10 × 10/21 × 10 = 100/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
80/30 = 80 × 7/30 × 7 = 560/210
Add the two like fractions:
100/210 + 560/210 = 100 + 560/210 = 660/210
660/210 simplified gives 22/7
So, 10/21 + 80/30 = 22/7
In mixed form: 31/7

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