Multiple choice

Directions: Compare Quantity A and Quantity B, using additional information centered above the two quantities if such information is given, and select one of the following four answer choices: Quantity A Quantity B Number of ways to select 2 balls at random from 30 balls 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 than quantity B.

  2. Quantity B is greater than quantity A.

  3. Both quantities are equal.

  4. The relationship between the quantities cannot be determined.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Quantity A: Choosing 2 from 30 is 30C2 = (30*29)/2 = 435. Quantity B: Choosing 1 red from 15 and 1 white from 15 is 15 * 15 = 225. Since 435 > 225, A is greater.

AI explanation

Using the combinations formula, Quantity A is 30C2, which evaluates to 30 times 29 divided by 2 for 435 ways. Quantity B requires selecting one red and one white ball, giving 15C1 times 15C1 for 225 ways. Comparing the two values, 435 is greater than 225, so Quantity A is greater.

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