Answers

Add 72/80 and 45/40

1^st number: 72/80, 2^nd number: 1 5/40

72/80 + 45/40 is 81/40.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 40 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 80 × 1 = 80,
   72/80 = 72 × 1/80 × 1 = 72/80
3. Likewise, for the 2nd fraction, since 40 × 2 = 80,
   45/40 = 45 × 2/40 × 2 = 90/80
4. Add the two like fractions:
   72/80 + 90/80 = 72 + 90/80 = 162/80
5. 162/80 simplified gives 81/40
6. So, 72/80 + 45/40 = 81/40
   In mixed form: 21/40

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