Add 90/27 and 21/80, Solve 3 9/27 + 21/80 as a fraction

Add 90/27 and 21/80

1^st number: 3 9/27, 2^nd number: 21/80

90/27 + 21/80 is 863/240.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 80 is 2160

Next, find the equivalent fraction of both fractional numbers with denominator 2160
For the 1st fraction, since 27 × 80 = 2160,
90/27 = 90 × 80/27 × 80 = 7200/2160
Likewise, for the 2nd fraction, since 80 × 27 = 2160,
21/80 = 21 × 27/80 × 27 = 567/2160
Add the two like fractions:
7200/2160 + 567/2160 = 7200 + 567/2160 = 7767/2160
7767/2160 simplified gives 863/240
So, 90/27 + 21/80 = 863/240
In mixed form: 3143/240

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