Answers

Add 42/80 and 54/45

1^st number: 42/80, 2^nd number: 1 9/45

42/80 + 54/45 is 69/40.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 45 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 80 × 9 = 720,
   42/80 = 42 × 9/80 × 9 = 378/720
3. Likewise, for the 2nd fraction, since 45 × 16 = 720,
   54/45 = 54 × 16/45 × 16 = 864/720
4. Add the two like fractions:
   378/720 + 864/720 = 378 + 864/720 = 1242/720
5. 1242/720 simplified gives 69/40
6. So, 42/80 + 54/45 = 69/40
   In mixed form: 129/40

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