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

Add 72/21 and 6/9

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

72/21 + 6/9 is 86/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
6/9 = 6 × 7/9 × 7 = 42/63
Add the two like fractions:
216/63 + 42/63 = 216 + 42/63 = 258/63
258/63 simplified gives 86/21
So, 72/21 + 6/9 = 86/21
In mixed form: 42/21

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