Add 2/18 and 70/21, Solve 2/18 + 3 7/21 as a fraction

Add 2/18 and 70/21

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

2/18 + 70/21 is 31/9.

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,
2/18 = 2 × 7/18 × 7 = 14/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Add the two like fractions:
14/126 + 420/126 = 14 + 420/126 = 434/126
434/126 simplified gives 31/9
So, 2/18 + 70/21 = 31/9
In mixed form: 34/9

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