Add 42/12 and 72/90, Solve 3 6/12 + 72/90 as a fraction

Add 42/12 and 72/90

1^st number: 3 6/12, 2^nd number: 72/90

42/12 + 72/90 is 43/10.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 12 × 15 = 180,
42/12 = 42 × 15/12 × 15 = 630/180
Likewise, for the 2nd fraction, since 90 × 2 = 180,
72/90 = 72 × 2/90 × 2 = 144/180
Add the two like fractions:
630/180 + 144/180 = 630 + 144/180 = 774/180
774/180 simplified gives 43/10
So, 42/12 + 72/90 = 43/10
In mixed form: 43/10

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