Add 15/18 and 90/7, Solve 15/18 + 12 6/7 as a fraction

Add 15/18 and 90/7

1^st number: 15/18, 2^nd number: 12 6/7

15/18 + 90/7 is 575/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 7 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
90/7 = 90 × 18/7 × 18 = 1620/126
Add the two like fractions:
105/126 + 1620/126 = 105 + 1620/126 = 1725/126
1725/126 simplified gives 575/42
So, 15/18 + 90/7 = 575/42
In mixed form: 1329/42

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