Add 48/15 and 21/84, Solve 3 3/15 + 21/84 as a fraction

Add 48/15 and 21/84

1^st number: 3 3/15, 2^nd number: 21/84

48/15 + 21/84 is 69/20.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
48/15 = 48 × 28/15 × 28 = 1344/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
1344/420 + 105/420 = 1344 + 105/420 = 1449/420
1449/420 simplified gives 69/20
So, 48/15 + 21/84 = 69/20
In mixed form: 39/20

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