Add 12/18 and 70/21, Solve 12/18 + 3 7/21 as a fraction

Add 12/18 and 70/21

1^st number: 12/18, 2^nd number: 3 7/21

12/18 + 70/21 is 4/1.

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,
12/18 = 12 × 7/18 × 7 = 84/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Add the two like fractions:
84/126 + 420/126 = 84 + 420/126 = 504/126
504/126 simplified gives 4/1
So, 12/18 + 70/21 = 4/1

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