Add 21/2 and 30/15, Solve 10 1/2 + 2 0/15 as a fraction

Add 21/2 and 30/15

1^st number: 10 1/2, 2^nd number: 2 0/15

21/2 + 30/15 is 25/2.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 15 is 30

Next, find the equivalent fraction of both fractional numbers with denominator 30
For the 1st fraction, since 2 × 15 = 30,
21/2 = 21 × 15/2 × 15 = 315/30
Likewise, for the 2nd fraction, since 15 × 2 = 30,
30/15 = 30 × 2/15 × 2 = 60/30
Add the two like fractions:
315/30 + 60/30 = 315 + 60/30 = 375/30
375/30 simplified gives 25/2
So, 21/2 + 30/15 = 25/2
In mixed form: 121/2

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