Answers

Add 81/20 and 21/90

1^st number: 4 1/20, 2^nd number: 21/90

81/20 + 21/90 is 257/60.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 90 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 20 × 9 = 180,
   81/20 = 81 × 9/20 × 9 = 729/180
3. Likewise, for the 2nd fraction, since 90 × 2 = 180,
   21/90 = 21 × 2/90 × 2 = 42/180
4. Add the two like fractions:
   729/180 + 42/180 = 729 + 42/180 = 771/180
5. 771/180 simplified gives 257/60
6. So, 81/20 + 21/90 = 257/60
   In mixed form: 417/60

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