Add 72/20 and 7/84, Solve 3 12/20 + 7/84 as a fraction

Add 72/20 and 7/84

1^st number: 3 12/20, 2^nd number: 7/84

72/20 + 7/84 is 221/60.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
7/84 = 7 × 5/84 × 5 = 35/420
Add the two like fractions:
1512/420 + 35/420 = 1512 + 35/420 = 1547/420
1547/420 simplified gives 221/60
So, 72/20 + 7/84 = 221/60
In mixed form: 341/60

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