Answers

Add 21/70 and 40/60

21/70 + 40/60 is 29/30.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 60 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 70 × 6 = 420,
   21/70 = 21 × 6/70 × 6 = 126/420
3. Likewise, for the 2nd fraction, since 60 × 7 = 420,
   40/60 = 40 × 7/60 × 7 = 280/420
4. Add the two like fractions:
   126/420 + 280/420 = 126 + 280/420 = 406/420
5. 406/420 simplified gives 29/30
6. So, 21/70 + 40/60 = 29/30

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