Answers

Add 20/21 and 45/60

20/21 + 45/60 is 143/84.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 60 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 21 × 20 = 420,
   20/21 = 20 × 20/21 × 20 = 400/420
3. Likewise, for the 2nd fraction, since 60 × 7 = 420,
   45/60 = 45 × 7/60 × 7 = 315/420
4. Add the two like fractions:
   400/420 + 315/420 = 400 + 315/420 = 715/420
5. 715/420 simplified gives 143/84
6. So, 20/21 + 45/60 = 143/84
   In mixed form: 159/84

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