Answers

Add 40/42 and 4/21

40/42 + 4/21 is 8/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 21 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 42 × 1 = 42,
   40/42 = 40 × 1/42 × 1 = 40/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   4/21 = 4 × 2/21 × 2 = 8/42
4. Add the two like fractions:
   40/42 + 8/42 = 40 + 8/42 = 48/42
5. 48/42 simplified gives 8/7
6. So, 40/42 + 4/21 = 8/7
   In mixed form: 11/7

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