Add 21/12 and 80/35, Solve 1 9/12 + 2 10/35 as a fraction

Add 21/12 and 80/35

1^st number: 1 9/12, 2^nd number: 2 10/35

21/12 + 80/35 is 113/28.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 35 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420
Likewise, for the 2nd fraction, since 35 × 12 = 420,
80/35 = 80 × 12/35 × 12 = 960/420
Add the two like fractions:
735/420 + 960/420 = 735 + 960/420 = 1695/420
1695/420 simplified gives 113/28
So, 21/12 + 80/35 = 113/28
In mixed form: 41/28

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