Add 21/2 and 15/80, Solve 10 1/2 + 15/80 as a fraction

Add 21/2 and 15/80

1^st number: 10 1/2, 2^nd number: 15/80

21/2 + 15/80 is 171/16.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 2 × 40 = 80,
21/2 = 21 × 40/2 × 40 = 840/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
15/80 = 15 × 1/80 × 1 = 15/80
Add the two like fractions:
840/80 + 15/80 = 840 + 15/80 = 855/80
855/80 simplified gives 171/16
So, 21/2 + 15/80 = 171/16
In mixed form: 1011/16

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