Answers

Add 25/40 and 21/84

25/40 + 21/84 is 7/8.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 84 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   25/40 = 25 × 21/40 × 21 = 525/840
3. Likewise, for the 2nd fraction, since 84 × 10 = 840,
   21/84 = 21 × 10/84 × 10 = 210/840
4. Add the two like fractions:
   525/840 + 210/840 = 525 + 210/840 = 735/840
5. 735/840 simplified gives 7/8
6. So, 25/40 + 21/84 = 7/8

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