Add 84/21 and 54/72, Solve 4 0/21 + 54/72 as a fraction

Add 84/21 and 54/72

1^st number: 4 0/21, 2^nd number: 54/72

84/21 + 54/72 is 19/4.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
84/21 = 84 × 24/21 × 24 = 2016/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
54/72 = 54 × 7/72 × 7 = 378/504
Add the two like fractions:
2016/504 + 378/504 = 2016 + 378/504 = 2394/504
2394/504 simplified gives 19/4
So, 84/21 + 54/72 = 19/4
In mixed form: 43/4

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