Multiple choice

The average (arithmetic mean) weight of 4 boys is 90 pounds. Two of the four boys among them weigh 80 and 100 pounds, respectively. Quantity A The average weight of the other two boys (in pounds) Quantity B 90

  1. Quantity A is greater.

  2. Quantity B is greater.

  3. The two quantities are equal.

  4. The relationship cannot be determined from the information given.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Total weight of 4 boys = 4 * 90 = 360. Sum of two boys = 80 + 100 = 180. Sum of other two = 360 - 180 = 180. Average of other two = 180 / 2 = 90. Quantity A = 90, Quantity B = 90.

AI explanation

The total weight of all 4 boys is 4 multiplied by 90, which equals 360 pounds. The combined weight of the two known boys is 80 plus 100, giving 180 pounds. The total weight of the other two boys is 360 minus 180, which is 180 pounds, and their average is 180 divided by 2, yielding 90 pounds. Since Quantity A is 90 and Quantity B is 90, the two quantities are equal.

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