Add 80/15 and 21/84, Solve 5 5/15 + 21/84 as a fraction

Add 80/15 and 21/84

1^st number: 5 5/15, 2^nd number: 21/84

80/15 + 21/84 is 67/12.

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,
80/15 = 80 × 28/15 × 28 = 2240/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
2240/420 + 105/420 = 2240 + 105/420 = 2345/420
2345/420 simplified gives 67/12
So, 80/15 + 21/84 = 67/12
In mixed form: 57/12

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