Answers

Add 20/84 and 42/72

20/84 + 42/72 is 23/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 72 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 84 × 6 = 504,
   20/84 = 20 × 6/84 × 6 = 120/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   42/72 = 42 × 7/72 × 7 = 294/504
4. Add the two like fractions:
   120/504 + 294/504 = 120 + 294/504 = 414/504
5. 414/504 simplified gives 23/28
6. So, 20/84 + 42/72 = 23/28

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