Answers

Add 30/70 and 81/72

1^st number: 30/70, 2^nd number: 1 9/72

30/70 + 81/72 is 87/56.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 72 is 2520
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2520
2. For the 1st fraction, since 70 × 36 = 2520,
   30/70 = 30 × 36/70 × 36 = 1080/2520
3. Likewise, for the 2nd fraction, since 72 × 35 = 2520,
   81/72 = 81 × 35/72 × 35 = 2835/2520
4. Add the two like fractions:
   1080/2520 + 2835/2520 = 1080 + 2835/2520 = 3915/2520
5. 3915/2520 simplified gives 87/56
6. So, 30/70 + 81/72 = 87/56
   In mixed form: 131/56

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