Add 21/84 and 15/9, Solve 21/84 + 1 6/9 as a fraction

Add 21/84 and 15/9

1^st number: 21/84, 2^nd number: 1 6/9

21/84 + 15/9 is 23/12.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252
Likewise, for the 2nd fraction, since 9 × 28 = 252,
15/9 = 15 × 28/9 × 28 = 420/252
Add the two like fractions:
63/252 + 420/252 = 63 + 420/252 = 483/252
483/252 simplified gives 23/12
So, 21/84 + 15/9 = 23/12
In mixed form: 111/12

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