Answers

Add 72/84 and 21/70

72/84 + 21/70 is 81/70.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 70 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 84 × 5 = 420,
   72/84 = 72 × 5/84 × 5 = 360/420
3. Likewise, for the 2nd fraction, since 70 × 6 = 420,
   21/70 = 21 × 6/70 × 6 = 126/420
4. Add the two like fractions:
   360/420 + 126/420 = 360 + 126/420 = 486/420
5. 486/420 simplified gives 81/70
6. So, 72/84 + 21/70 = 81/70
   In mixed form: 111/70

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