Add 40/72 and 45/12, Solve 40/72 + 3 9/12 as a fraction

Add 40/72 and 45/12

1^st number: 40/72, 2^nd number: 3 9/12

40/72 + 45/12 is 155/36.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 12 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 72 × 1 = 72,
40/72 = 40 × 1/72 × 1 = 40/72
Likewise, for the 2nd fraction, since 12 × 6 = 72,
45/12 = 45 × 6/12 × 6 = 270/72
Add the two like fractions:
40/72 + 270/72 = 40 + 270/72 = 310/72
310/72 simplified gives 155/36
So, 40/72 + 45/12 = 155/36
In mixed form: 411/36

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