Add 12/3 and 45/21, Solve 4 0/3 + 2 3/21 as a fraction

Add 12/3 and 45/21

1^st number: 4 0/3, 2^nd number: 2 3/21

12/3 + 45/21 is 43/7.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21

Next, find the equivalent fraction of both fractional numbers with denominator 21
For the 1st fraction, since 3 × 7 = 21,
12/3 = 12 × 7/3 × 7 = 84/21
Likewise, for the 2nd fraction, since 21 × 1 = 21,
45/21 = 45 × 1/21 × 1 = 45/21
Add the two like fractions:
84/21 + 45/21 = 84 + 45/21 = 129/21
129/21 simplified gives 43/7
So, 12/3 + 45/21 = 43/7
In mixed form: 61/7

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