Add 21/18 and 60/70, Solve 1 3/18 + 60/70 as a fraction

Add 21/18 and 60/70

1^st number: 1 3/18, 2^nd number: 60/70

21/18 + 60/70 is 85/42.

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,
60/70 = 60 × 9/70 × 9 = 540/630
Add the two like fractions:
735/630 + 540/630 = 735 + 540/630 = 1275/630
1275/630 simplified gives 85/42
So, 21/18 + 60/70 = 85/42
In mixed form: 21/42

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