Answers

Add 70/42 and 21/40

1^st number: 1 28/42, 2^nd number: 21/40

70/42 + 21/40 is 263/120.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   70/42 = 70 × 20/42 × 20 = 1400/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   21/40 = 21 × 21/40 × 21 = 441/840
4. Add the two like fractions:
   1400/840 + 441/840 = 1400 + 441/840 = 1841/840
5. 1841/840 simplified gives 263/120
6. So, 70/42 + 21/40 = 263/120
   In mixed form: 223/120

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