Answers

Add 21/80 and 24/70

21/80 + 24/70 is 339/560.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 70 is 560
   
   Next, find the equivalent fraction of both fractional numbers with denominator 560
2. For the 1st fraction, since 80 × 7 = 560,
   21/80 = 21 × 7/80 × 7 = 147/560
3. Likewise, for the 2nd fraction, since 70 × 8 = 560,
   24/70 = 24 × 8/70 × 8 = 192/560
4. Add the two like fractions:
   147/560 + 192/560 = 147 + 192/560 = 339/560
5. So, 21/80 + 24/70 = 339/560

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