Add 45/12 and 20/8, Solve 3 9/12 + 2 4/8 as a fraction

Add 45/12 and 20/8

1^st number: 3 9/12, 2^nd number: 2 4/8

45/12 + 20/8 is 25/4.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 8 is 24

Next, find the equivalent fraction of both fractional numbers with denominator 24
For the 1st fraction, since 12 × 2 = 24,
45/12 = 45 × 2/12 × 2 = 90/24
Likewise, for the 2nd fraction, since 8 × 3 = 24,
20/8 = 20 × 3/8 × 3 = 60/24
Add the two like fractions:
90/24 + 60/24 = 90 + 60/24 = 150/24
150/24 simplified gives 25/4
So, 45/12 + 20/8 = 25/4
In mixed form: 61/4

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