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

Add 21/12 and 9/30

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

21/12 + 9/30 is 41/20.

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,
9/30 = 9 × 2/30 × 2 = 18/60
Add the two like fractions:
105/60 + 18/60 = 105 + 18/60 = 123/60
123/60 simplified gives 41/20
So, 21/12 + 9/30 = 41/20
In mixed form: 21/20

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