Answers

Add 21/42 and 90/72

1^st number: 21/42, 2^nd number: 1 18/72

21/42 + 90/72 is 7/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 72 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 42 × 12 = 504,
   21/42 = 21 × 12/42 × 12 = 252/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   90/72 = 90 × 7/72 × 7 = 630/504
4. Add the two like fractions:
   252/504 + 630/504 = 252 + 630/504 = 882/504
5. 882/504 simplified gives 7/4
6. So, 21/42 + 90/72 = 7/4
   In mixed form: 13/4

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