Add 21/5 and 15/12, Solve 4 1/5 + 1 3/12 as a fraction

Add 21/5 and 15/12

1^st number: 4 1/5, 2^nd number: 1 3/12

21/5 + 15/12 is 109/20.

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,
15/12 = 15 × 5/12 × 5 = 75/60
Add the two like fractions:
252/60 + 75/60 = 252 + 75/60 = 327/60
327/60 simplified gives 109/20
So, 21/5 + 15/12 = 109/20
In mixed form: 59/20

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