Answers

Add 42/84 and 7/20

42/84 + 7/20 is 17/20.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 84 × 5 = 420,
   42/84 = 42 × 5/84 × 5 = 210/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   7/20 = 7 × 21/20 × 21 = 147/420
4. Add the two like fractions:
   210/420 + 147/420 = 210 + 147/420 = 357/420
5. 357/420 simplified gives 17/20
6. So, 42/84 + 7/20 = 17/20

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