Add 24/21 and 54/12, Solve 1 3/21 + 4 6/12 as a fraction

Add 24/21 and 54/12

1^st number: 1 3/21, 2^nd number: 4 6/12

24/21 + 54/12 is 79/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
24/21 = 24 × 4/21 × 4 = 96/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
54/12 = 54 × 7/12 × 7 = 378/84
Add the two like fractions:
96/84 + 378/84 = 96 + 378/84 = 474/84
474/84 simplified gives 79/14
So, 24/21 + 54/12 = 79/14
In mixed form: 59/14

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