Multiple choice

A surprise test was conducted in a class of 21 students and the average marks obtained by 21 students were 45. Out of this, the average marks obtained by first 10 students were 42 while last 10 students obtained 43. What is the marks obtained by the 11th student in the class?

  1. 80

  2. 95

  3. 96

  4. 97
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total marks = 21 * 45 = 945. First 10 = 10 * 42 = 420. Last 10 = 10 * 43 = 430. 11th student = 945 - (420 + 430) = 945 - 850 = 95.

AI explanation

The total marks for all 21 students is 21 multiplied by 45, which equals 945. The combined marks of the first 10 and last 10 students is 420 plus 430, totaling 850. Subtracting the combined marks of these 20 students from the class total gives the 11th student's marks: 945 minus 850 equals 95.

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