Add 18/21 and 54/9, Solve 18/21 + 6 0/9 as a fraction

Add 18/21 and 54/9

1^st number: 18/21, 2^nd number: 6 0/9

18/21 + 54/9 is 48/7.

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,
18/21 = 18 × 3/21 × 3 = 54/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
54/9 = 54 × 7/9 × 7 = 378/63
Add the two like fractions:
54/63 + 378/63 = 54 + 378/63 = 432/63
432/63 simplified gives 48/7
So, 18/21 + 54/9 = 48/7
In mixed form: 66/7

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