Add 27/21 and 80/72, Solve 1 6/21 + 1 8/72 as a fraction

Add 27/21 and 80/72

1^st number: 1 6/21, 2^nd number: 1 8/72

27/21 + 80/72 is 151/63.

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,
27/21 = 27 × 24/21 × 24 = 648/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
80/72 = 80 × 7/72 × 7 = 560/504
Add the two like fractions:
648/504 + 560/504 = 648 + 560/504 = 1208/504
1208/504 simplified gives 151/63
So, 27/21 + 80/72 = 151/63
In mixed form: 225/63

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