Add 45/12 and 27/40, Solve 3 9/12 + 27/40 as a fraction

Add 45/12 and 27/40

1^st number: 3 9/12, 2^nd number: 27/40

45/12 + 27/40 is 177/40.

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,
27/40 = 27 × 3/40 × 3 = 81/120
Add the two like fractions:
450/120 + 81/120 = 450 + 81/120 = 531/120
531/120 simplified gives 177/40
So, 45/12 + 27/40 = 177/40
In mixed form: 417/40

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