Add 81/72 and 54/42, Solve 1 9/72 + 1 12/42 as a fraction

Add 81/72 and 54/42

1^st number: 1 9/72, 2^nd number: 1 12/42

81/72 + 54/42 is 135/56.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504
Likewise, for the 2nd fraction, since 42 × 12 = 504,
54/42 = 54 × 12/42 × 12 = 648/504
Add the two like fractions:
567/504 + 648/504 = 567 + 648/504 = 1215/504
1215/504 simplified gives 135/56
So, 81/72 + 54/42 = 135/56
In mixed form: 223/56

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