Add 5/18 and 70/21, Solve 5/18 + 3 7/21 as a fraction

Add 5/18 and 70/21

1^st number: 5/18, 2^nd number: 3 7/21

5/18 + 70/21 is 65/18.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
5/18 = 5 × 7/18 × 7 = 35/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Add the two like fractions:
35/126 + 420/126 = 35 + 420/126 = 455/126
455/126 simplified gives 65/18
So, 5/18 + 70/21 = 65/18
In mixed form: 311/18

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