Answers

Add 81/20 and 21/70

1^st number: 4 1/20, 2^nd number: 21/70

81/20 + 21/70 is 87/20.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 70 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 20 × 7 = 140,
   81/20 = 81 × 7/20 × 7 = 567/140
3. Likewise, for the 2nd fraction, since 70 × 2 = 140,
   21/70 = 21 × 2/70 × 2 = 42/140
4. Add the two like fractions:
   567/140 + 42/140 = 567 + 42/140 = 609/140
5. 609/140 simplified gives 87/20
6. So, 81/20 + 21/70 = 87/20
   In mixed form: 47/20

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