Add 15/12 and 18/7, Solve 1 3/12 + 2 4/7 as a fraction

Add 15/12 and 18/7

1^st number: 1 3/12, 2^nd number: 2 4/7

15/12 + 18/7 is 107/28.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
18/7 = 18 × 12/7 × 12 = 216/84
Add the two like fractions:
105/84 + 216/84 = 105 + 216/84 = 321/84
321/84 simplified gives 107/28
So, 15/12 + 18/7 = 107/28
In mixed form: 323/28

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