Answers

Add 21/84 and 5/90

21/84 + 5/90 is 11/36.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 90 is 1260
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1260
2. For the 1st fraction, since 84 × 15 = 1260,
   21/84 = 21 × 15/84 × 15 = 315/1260
3. Likewise, for the 2nd fraction, since 90 × 14 = 1260,
   5/90 = 5 × 14/90 × 14 = 70/1260
4. Add the two like fractions:
   315/1260 + 70/1260 = 315 + 70/1260 = 385/1260
5. 385/1260 simplified gives 11/36
6. So, 21/84 + 5/90 = 11/36

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