Add 21/12 and 20/14, Solve 1 9/12 + 1 6/14 as a fraction

Add 21/12 and 20/14

1^st number: 1 9/12, 2^nd number: 1 6/14

21/12 + 20/14 is 89/28.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 14 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84
Likewise, for the 2nd fraction, since 14 × 6 = 84,
20/14 = 20 × 6/14 × 6 = 120/84
Add the two like fractions:
147/84 + 120/84 = 147 + 120/84 = 267/84
267/84 simplified gives 89/28
So, 21/12 + 20/14 = 89/28
In mixed form: 35/28

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