Answers

Add 90/12 and 21/42

1^st number: 7 6/12, 2^nd number: 21/42

90/12 + 21/42 is 8/1.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 42 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 12 × 7 = 84,
   90/12 = 90 × 7/12 × 7 = 630/84
3. Likewise, for the 2nd fraction, since 42 × 2 = 84,
   21/42 = 21 × 2/42 × 2 = 42/84
4. Add the two like fractions:
   630/84 + 42/84 = 630 + 42/84 = 672/84
5. 672/84 simplified gives 8/1
6. So, 90/12 + 21/42 = 8/1

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