Multiple choice

If the average weight of $6$ students is $50$ kg, that of $2$ students is $51$ kg and that of rest of $2$ students is $55$ kg, then the average weight of all the students is

  1. $61$ kg
  2. $51.5$ kg
  3. $52$ kg
  4. $51.2$ kg
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total weight = (6 * 50) + (2 * 51) + (2 * 55) = 300 + 102 + 110 = 512. Total students = 6 + 2 + 2 = 10. Average = 512 / 10 = 51.2.

AI explanation

Using the formula for weighted average, the total weight is (6 times 50) + (2 times 51) + (2 times 55) = 300 + 102 + 110 = 512 kg. Since the total number of students is 10, the average weight is 512 divided by 10, which equals 51.2 kg. The correct average weight is 51.2 kg.

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