Add 21/18 and 5/70, Solve 1 3/18 + 5/70 as a fraction

Add 21/18 and 5/70

1^st number: 1 3/18, 2^nd number: 5/70

21/18 + 5/70 is 26/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
5/70 = 5 × 9/70 × 9 = 45/630
Add the two like fractions:
735/630 + 45/630 = 735 + 45/630 = 780/630
780/630 simplified gives 26/21
So, 21/18 + 5/70 = 26/21
In mixed form: 15/21

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