Add 21/12 and 10/20, Solve 1 9/12 + 10/20 as a fraction

Add 21/12 and 10/20

1^st number: 1 9/12, 2^nd number: 10/20

21/12 + 10/20 is 9/4.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 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 20 × 3 = 60,
10/20 = 10 × 3/20 × 3 = 30/60
Add the two like fractions:
105/60 + 30/60 = 105 + 30/60 = 135/60
135/60 simplified gives 9/4
So, 21/12 + 10/20 = 9/4
In mixed form: 21/4

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