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

Add 9/12 and 21/10

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

9/12 + 21/10 is 57/20.

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,
9/12 = 9 × 5/12 × 5 = 45/60
Likewise, for the 2nd fraction, since 10 × 6 = 60,
21/10 = 21 × 6/10 × 6 = 126/60
Add the two like fractions:
45/60 + 126/60 = 45 + 126/60 = 171/60
171/60 simplified gives 57/20
So, 9/12 + 21/10 = 57/20
In mixed form: 217/20

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