Add 4/84 and 63/20, Solve 4/84 + 3 3/20 as a fraction

Add 4/84 and 63/20

1^st number: 4/84, 2^nd number: 3 3/20

4/84 + 63/20 is 1343/420.

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,
4/84 = 4 × 5/84 × 5 = 20/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
63/20 = 63 × 21/20 × 21 = 1323/420
Add the two like fractions:
20/420 + 1323/420 = 20 + 1323/420 = 1343/420
So, 4/84 + 63/20 = 1343/420
In mixed form: 383/420

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