Add 72/21 and 24/18, Solve 3 9/21 + 1 6/18 as a fraction

Add 72/21 and 24/18

1^st number: 3 9/21, 2^nd number: 1 6/18

72/21 + 24/18 is 100/21.

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,
72/21 = 72 × 6/21 × 6 = 432/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
24/18 = 24 × 7/18 × 7 = 168/126
Add the two like fractions:
432/126 + 168/126 = 432 + 168/126 = 600/126
600/126 simplified gives 100/21
So, 72/21 + 24/18 = 100/21
In mixed form: 416/21

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