Add 30/21 and 9/4, Solve 1 9/21 + 2 1/4 as a fraction

Add 30/21 and 9/4

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

30/21 + 9/4 is 103/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
9/4 = 9 × 21/4 × 21 = 189/84
Add the two like fractions:
120/84 + 189/84 = 120 + 189/84 = 309/84
309/84 simplified gives 103/28
So, 30/21 + 9/4 = 103/28
In mixed form: 319/28

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