Add 30/21 and 75/28, Solve 1 9/21 + 2 19/28 as a fraction

Add 30/21 and 75/28

1^st number: 1 9/21, 2^nd number: 2 19/28

30/21 + 75/28 is 115/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 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 28 × 3 = 84,
75/28 = 75 × 3/28 × 3 = 225/84
Add the two like fractions:
120/84 + 225/84 = 120 + 225/84 = 345/84
345/84 simplified gives 115/28
So, 30/21 + 75/28 = 115/28
In mixed form: 43/28

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