Add 1/84 and 72/20, Solve 1/84 + 3 12/20 as a fraction

Add 1/84 and 72/20

1^st number: 1/84, 2^nd number: 3 12/20

1/84 + 72/20 is 1517/420.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
1/84 = 1 × 5/84 × 5 = 5/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Add the two like fractions:
5/420 + 1512/420 = 5 + 1512/420 = 1517/420
So, 1/84 + 72/20 = 1517/420
In mixed form: 3257/420

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