Answers

Add 90/72 and 20/42

1^st number: 1 18/72, 2^nd number: 20/42

90/72 + 20/42 is 145/84.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 42 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 72 × 7 = 504,
   90/72 = 90 × 7/72 × 7 = 630/504
3. Likewise, for the 2nd fraction, since 42 × 12 = 504,
   20/42 = 20 × 12/42 × 12 = 240/504
4. Add the two like fractions:
   630/504 + 240/504 = 630 + 240/504 = 870/504
5. 870/504 simplified gives 145/84
6. So, 90/72 + 20/42 = 145/84
   In mixed form: 161/84

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