Multiple choice

The average of 11 numbers is 50. If the average of first 10 numbers is 53, then find the eleventh number.

  1. 40

  2. 20

  3. 24

  4. 30

  5. 29
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total of 11 numbers = 11 * 50 = 550. Total of first 10 numbers = 10 * 53 = 530. The eleventh number = 550 - 530 = 20.

AI explanation

The total sum of all 11 numbers is 11 multiplied by 50, which equals 550. The total sum of the first 10 numbers is 10 multiplied by 53, equaling 530. The eleventh number is the total sum of all numbers minus the sum of the first ten numbers, so 550 minus 530 equals 20. The result is B.

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