Add 20/28 and 45/12, Solve 20/28 + 3 9/12 as a fraction

Add 20/28 and 45/12

1^st number: 20/28, 2^nd number: 3 9/12

20/28 + 45/12 is 125/28.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
20/28 = 20 × 3/28 × 3 = 60/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84
Add the two like fractions:
60/84 + 315/84 = 60 + 315/84 = 375/84
375/84 simplified gives 125/28
So, 20/28 + 45/12 = 125/28
In mixed form: 413/28

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