Add 90/80 and 21/12, Solve 1 10/80 + 1 9/12 as a fraction

Add 90/80 and 21/12

1^st number: 1 10/80, 2^nd number: 1 9/12

90/80 + 21/12 is 23/8.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
90/80 = 90 × 3/80 × 3 = 270/240
Likewise, for the 2nd fraction, since 12 × 20 = 240,
21/12 = 21 × 20/12 × 20 = 420/240
Add the two like fractions:
270/240 + 420/240 = 270 + 420/240 = 690/240
690/240 simplified gives 23/8
So, 90/80 + 21/12 = 23/8
In mixed form: 27/8

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