Add 21/5 and 9/12, Solve 4 1/5 + 9/12 as a fraction

Add 21/5 and 9/12

1^st number: 4 1/5, 2^nd number: 9/12

21/5 + 9/12 is 99/20.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 12 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 5 × 12 = 60,
21/5 = 21 × 12/5 × 12 = 252/60
Likewise, for the 2nd fraction, since 12 × 5 = 60,
9/12 = 9 × 5/12 × 5 = 45/60
Add the two like fractions:
252/60 + 45/60 = 252 + 45/60 = 297/60
297/60 simplified gives 99/20
So, 21/5 + 9/12 = 99/20
In mixed form: 419/20

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