Add 12/90 and 81/42, Solve 12/90 + 1 39/42 as a fraction

Add 12/90 and 81/42

1^st number: 12/90, 2^nd number: 1 39/42

12/90 + 81/42 is 433/210.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
12/90 = 12 × 7/90 × 7 = 84/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
81/42 = 81 × 15/42 × 15 = 1215/630
Add the two like fractions:
84/630 + 1215/630 = 84 + 1215/630 = 1299/630
1299/630 simplified gives 433/210
So, 12/90 + 81/42 = 433/210
In mixed form: 213/210

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