Add 84/20 and 12/21, Solve 4 4/20 + 12/21 as a fraction

Add 84/20 and 12/21

1^st number: 4 4/20, 2^nd number: 12/21

84/20 + 12/21 is 167/35.

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,
84/20 = 84 × 21/20 × 21 = 1764/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
12/21 = 12 × 20/21 × 20 = 240/420
Add the two like fractions:
1764/420 + 240/420 = 1764 + 240/420 = 2004/420
2004/420 simplified gives 167/35
So, 84/20 + 12/21 = 167/35
In mixed form: 427/35

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