Answers

Add 21/54 and 90/80

1^st number: 21/54, 2^nd number: 1 10/80

21/54 + 90/80 is 109/72.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 80 is 2160
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2160
2. For the 1st fraction, since 54 × 40 = 2160,
   21/54 = 21 × 40/54 × 40 = 840/2160
3. Likewise, for the 2nd fraction, since 80 × 27 = 2160,
   90/80 = 90 × 27/80 × 27 = 2430/2160
4. Add the two like fractions:
   840/2160 + 2430/2160 = 840 + 2430/2160 = 3270/2160
5. 3270/2160 simplified gives 109/72
6. So, 21/54 + 90/80 = 109/72
   In mixed form: 137/72

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