Add 30/20 and 9/21, Solve 1 10/20 + 9/21 as a fraction

Add 30/20 and 9/21

1^st number: 1 10/20, 2^nd number: 9/21

30/20 + 9/21 is 27/14.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
30/20 = 30 × 21/20 × 21 = 630/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
9/21 = 9 × 20/21 × 20 = 180/420
Add the two like fractions:
630/420 + 180/420 = 630 + 180/420 = 810/420
810/420 simplified gives 27/14
So, 30/20 + 9/21 = 27/14
In mixed form: 113/14

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