Add 12/70 and 21/18, Solve 12/70 + 1 3/18 as a fraction

Add 12/70 and 21/18

1^st number: 12/70, 2^nd number: 1 3/18

12/70 + 21/18 is 281/210.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
12/70 = 12 × 9/70 × 9 = 108/630
Likewise, for the 2nd fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630
Add the two like fractions:
108/630 + 735/630 = 108 + 735/630 = 843/630
843/630 simplified gives 281/210
So, 12/70 + 21/18 = 281/210
In mixed form: 171/210

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