Answers

Add 42/80 and 70/81

42/80 + 70/81 is 4501/3240.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 81 is 6480
   
   Next, find the equivalent fraction of both fractional numbers with denominator 6480
2. For the 1st fraction, since 80 × 81 = 6480,
   42/80 = 42 × 81/80 × 81 = 3402/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   70/81 = 70 × 80/81 × 80 = 5600/6480
4. Add the two like fractions:
   3402/6480 + 5600/6480 = 3402 + 5600/6480 = 9002/6480
5. 9002/6480 simplified gives 4501/3240
6. So, 42/80 + 70/81 = 4501/3240
   In mixed form: 11261/3240

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