Add 70/21 and 21/18, Solve 3 7/21 + 1 3/18 as a fraction

Add 70/21 and 21/18

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

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

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126
Add the two like fractions:
420/126 + 147/126 = 420 + 147/126 = 567/126
567/126 simplified gives 9/2
So, 70/21 + 21/18 = 9/2
In mixed form: 41/2

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