Add 54/14 and 21/84, Solve 3 12/14 + 21/84 as a fraction

Add 54/14 and 21/84

1^st number: 3 12/14, 2^nd number: 21/84

54/14 + 21/84 is 115/28.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 84 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 14 × 6 = 84,
54/14 = 54 × 6/14 × 6 = 324/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84
Add the two like fractions:
324/84 + 21/84 = 324 + 21/84 = 345/84
345/84 simplified gives 115/28
So, 54/14 + 21/84 = 115/28
In mixed form: 43/28

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