Add 6/21 and 72/20, Solve 6/21 + 3 12/20 as a fraction

Add 6/21 and 72/20

1^st number: 6/21, 2^nd number: 3 12/20

6/21 + 72/20 is 136/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
6/21 = 6 × 20/21 × 20 = 120/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Add the two like fractions:
120/420 + 1512/420 = 120 + 1512/420 = 1632/420
1632/420 simplified gives 136/35
So, 6/21 + 72/20 = 136/35
In mixed form: 331/35

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