Add 81/21 and 27/72, Solve 3 18/21 + 27/72 as a fraction

Add 81/21 and 27/72

1^st number: 3 18/21, 2^nd number: 27/72

81/21 + 27/72 is 237/56.

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,
81/21 = 81 × 24/21 × 24 = 1944/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
27/72 = 27 × 7/72 × 7 = 189/504
Add the two like fractions:
1944/504 + 189/504 = 1944 + 189/504 = 2133/504
2133/504 simplified gives 237/56
So, 81/21 + 27/72 = 237/56
In mixed form: 413/56

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