Add 21/12 and 12/10, Solve 1 9/12 + 1 2/10 as a fraction

Add 21/12 and 12/10

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

21/12 + 12/10 is 59/20.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 10 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 10 × 6 = 60,
12/10 = 12 × 6/10 × 6 = 72/60
Add the two like fractions:
105/60 + 72/60 = 105 + 72/60 = 177/60
177/60 simplified gives 59/20
So, 21/12 + 12/10 = 59/20
In mixed form: 219/20

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