Add 21/12 and 25/30, Solve 1 9/12 + 25/30 as a fraction

Add 21/12 and 25/30

1^st number: 1 9/12, 2^nd number: 25/30

21/12 + 25/30 is 31/12.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 30 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 30 × 2 = 60,
25/30 = 25 × 2/30 × 2 = 50/60
Add the two like fractions:
105/60 + 50/60 = 105 + 50/60 = 155/60
155/60 simplified gives 31/12
So, 21/12 + 25/30 = 31/12
In mixed form: 27/12

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