Add 9/12 and 21/14, Solve 9/12 + 1 7/14 as a fraction

Add 9/12 and 21/14

1^st number: 9/12, 2^nd number: 1 7/14

9/12 + 21/14 is 9/4.

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,
9/12 = 9 × 7/12 × 7 = 63/84
Likewise, for the 2nd fraction, since 14 × 6 = 84,
21/14 = 21 × 6/14 × 6 = 126/84
Add the two like fractions:
63/84 + 126/84 = 63 + 126/84 = 189/84
189/84 simplified gives 9/4
So, 9/12 + 21/14 = 9/4
In mixed form: 21/4

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