Add 81/2 and 45/12, Solve 40 1/2 + 3 9/12 as a fraction

Add 81/2 and 45/12

1^st number: 40 1/2, 2^nd number: 3 9/12

81/2 + 45/12 is 177/4.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 12 is 12

Next, find the equivalent fraction of both fractional numbers with denominator 12
For the 1st fraction, since 2 × 6 = 12,
81/2 = 81 × 6/2 × 6 = 486/12
Likewise, for the 2nd fraction, since 12 × 1 = 12,
45/12 = 45 × 1/12 × 1 = 45/12
Add the two like fractions:
486/12 + 45/12 = 486 + 45/12 = 531/12
531/12 simplified gives 177/4
So, 81/2 + 45/12 = 177/4
In mixed form: 441/4

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