Add 30/21 and 28/80, Solve 1 9/21 + 28/80 as a fraction

Add 30/21 and 28/80

1^st number: 1 9/21, 2^nd number: 28/80

30/21 + 28/80 is 249/140.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
30/21 = 30 × 80/21 × 80 = 2400/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
28/80 = 28 × 21/80 × 21 = 588/1680
Add the two like fractions:
2400/1680 + 588/1680 = 2400 + 588/1680 = 2988/1680
2988/1680 simplified gives 249/140
So, 30/21 + 28/80 = 249/140
In mixed form: 1109/140

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