Add 30/4 and 9/21, Solve 7 2/4 + 9/21 as a fraction

Add 30/4 and 9/21

1^st number: 7 2/4, 2^nd number: 9/21

30/4 + 9/21 is 111/14.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
30/4 = 30 × 21/4 × 21 = 630/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
9/21 = 9 × 4/21 × 4 = 36/84
Add the two like fractions:
630/84 + 36/84 = 630 + 36/84 = 666/84
666/84 simplified gives 111/14
So, 30/4 + 9/21 = 111/14
In mixed form: 713/14

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