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

Add 45/12 and 81/40

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

45/12 + 81/40 is 231/40.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 12 × 10 = 120,
45/12 = 45 × 10/12 × 10 = 450/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
81/40 = 81 × 3/40 × 3 = 243/120
Add the two like fractions:
450/120 + 243/120 = 450 + 243/120 = 693/120
693/120 simplified gives 231/40
So, 45/12 + 81/40 = 231/40
In mixed form: 531/40

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