Multiple choice

Average of ten numbers is 30. Later on it was observed that 15, 23 are wrongly taken as 51,32. Find the correct average?

  1. 21.3

  2. 14.6

  3. 25.5

  4. 6.6

  5. 23.3
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C Correct answer
Explanation

Initial sum = 10 * 30 = 300. Correct sum = 300 - 51 - 32 + 15 + 23 = 300 - 83 + 38 = 255. Correct average = 255 / 10 = 25.5.

AI explanation

The original sum of the ten numbers is 10 multiplied by 30, which equals 300. To find the correct sum, subtract the incorrect values 51 and 32, and add the correct values 15 and 23, resulting in a new sum of 255. Dividing 255 by 10 gives the correct average of 25.5.

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