Add 30/84 and 75/21, Solve 30/84 + 3 12/21 as a fraction

Add 30/84 and 75/21

1^st number: 30/84, 2^nd number: 3 12/21

30/84 + 75/21 is 55/14.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 84 × 1 = 84,
30/84 = 30 × 1/84 × 1 = 30/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
75/21 = 75 × 4/21 × 4 = 300/84
Add the two like fractions:
30/84 + 300/84 = 30 + 300/84 = 330/84
330/84 simplified gives 55/14
So, 30/84 + 75/21 = 55/14
In mixed form: 313/14

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