Add 45/21 and 9/12, Solve 2 3/21 + 9/12 as a fraction

Add 45/21 and 9/12

1^st number: 2 3/21, 2^nd number: 9/12

45/21 + 9/12 is 81/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
45/21 = 45 × 4/21 × 4 = 180/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
9/12 = 9 × 7/12 × 7 = 63/84
Add the two like fractions:
180/84 + 63/84 = 180 + 63/84 = 243/84
243/84 simplified gives 81/28
So, 45/21 + 9/12 = 81/28
In mixed form: 225/28

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