Add 54/21 and 42/9, Solve 2 12/21 + 4 6/9 as a fraction

Add 54/21 and 42/9

1^st number: 2 12/21, 2^nd number: 4 6/9

54/21 + 42/9 is 152/21.

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,
54/21 = 54 × 3/21 × 3 = 162/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63
Add the two like fractions:
162/63 + 294/63 = 162 + 294/63 = 456/63
456/63 simplified gives 152/21
So, 54/21 + 42/9 = 152/21
In mixed form: 75/21

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