Add 54/21 and 1/84, Solve 2 12/21 + 1/84 as a fraction

Add 54/21 and 1/84

1^st number: 2 12/21, 2^nd number: 1/84

54/21 + 1/84 is 31/12.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
54/21 = 54 × 4/21 × 4 = 216/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
1/84 = 1 × 1/84 × 1 = 1/84
Add the two like fractions:
216/84 + 1/84 = 216 + 1/84 = 217/84
217/84 simplified gives 31/12
So, 54/21 + 1/84 = 31/12
In mixed form: 27/12

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