Add 21/2 and 72/90, Solve 10 1/2 + 72/90 as a fraction

Add 21/2 and 72/90

1^st number: 10 1/2, 2^nd number: 72/90

21/2 + 72/90 is 113/10.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 90 is 90

Next, find the equivalent fraction of both fractional numbers with denominator 90
For the 1st fraction, since 2 × 45 = 90,
21/2 = 21 × 45/2 × 45 = 945/90
Likewise, for the 2nd fraction, since 90 × 1 = 90,
72/90 = 72 × 1/90 × 1 = 72/90
Add the two like fractions:
945/90 + 72/90 = 945 + 72/90 = 1017/90
1017/90 simplified gives 113/10
So, 21/2 + 72/90 = 113/10
In mixed form: 113/10

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