Add 90/80 and 21/8, Solve 1 10/80 + 2 5/8 as a fraction

Add 90/80 and 21/8

1^st number: 1 10/80, 2^nd number: 2 5/8

90/80 + 21/8 is 15/4.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 8 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 80 × 1 = 80,
90/80 = 90 × 1/80 × 1 = 90/80
Likewise, for the 2nd fraction, since 8 × 10 = 80,
21/8 = 21 × 10/8 × 10 = 210/80
Add the two like fractions:
90/80 + 210/80 = 90 + 210/80 = 300/80
300/80 simplified gives 15/4
So, 90/80 + 21/8 = 15/4
In mixed form: 33/4

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