Add 21/12 and 4/10, Solve 1 9/12 + 4/10 as a fraction

Add 21/12 and 4/10

1^st number: 1 9/12, 2^nd number: 4/10

21/12 + 4/10 is 43/20.

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,
4/10 = 4 × 6/10 × 6 = 24/60
Add the two like fractions:
105/60 + 24/60 = 105 + 24/60 = 129/60
129/60 simplified gives 43/20
So, 21/12 + 4/10 = 43/20
In mixed form: 23/20

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