Add 9/4 and 28/21, Solve 2 1/4 + 1 7/21 as a fraction

Add 9/4 and 28/21

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

9/4 + 28/21 is 43/12.

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,
9/4 = 9 × 21/4 × 21 = 189/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84
Add the two like fractions:
189/84 + 112/84 = 189 + 112/84 = 301/84
301/84 simplified gives 43/12
So, 9/4 + 28/21 = 43/12
In mixed form: 37/12

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