Answers

Add 21/40 and 75/70

1^st number: 21/40, 2^nd number: 1 5/70

21/40 + 75/70 is 447/280.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 70 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 40 × 7 = 280,
   21/40 = 21 × 7/40 × 7 = 147/280
3. Likewise, for the 2nd fraction, since 70 × 4 = 280,
   75/70 = 75 × 4/70 × 4 = 300/280
4. Add the two like fractions:
   147/280 + 300/280 = 147 + 300/280 = 447/280
5. So, 21/40 + 75/70 = 447/280
   In mixed form: 1167/280

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