Multiple choice

Quantity A Number of ways to select 2 balls at random from 30 balls Quantity B Number of ways to select 2 balls at random, one red and one white, when there are 15 red and 15 white balls

  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
A Correct answer
Explanation

Quantity A: 30C2 = (30*29)/2 = 435. Quantity B: 15C1 * 15C1 = 15 * 15 = 225. Since 435 > 225, Quantity A is greater.

AI explanation

Quantity A calculates the total combinations of selecting 2 balls from 30, which is 30 factorial divided by the product of 2 factorial and 28 factorial, equaling 435. Quantity B calculates the combinations of selecting 1 red and 1 white ball, which equals 15 multiplied by 15, giving 225. Since 435 is greater than 225, Quantity A is greater.

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