Add 21/12 and 27/5, Solve 1 9/12 + 5 2/5 as a fraction

Add 21/12 and 27/5

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

21/12 + 27/5 is 143/20.

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

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60
Likewise, for the 2nd fraction, since 5 × 12 = 60,
27/5 = 27 × 12/5 × 12 = 324/60
Add the two like fractions:
105/60 + 324/60 = 105 + 324/60 = 429/60
429/60 simplified gives 143/20
So, 21/12 + 27/5 = 143/20
In mixed form: 73/20

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