Question

4 multiple choice 4 points andy put 8 letter cards into a box. he reaches in, chooses a card, reads the letter, and returns it to the box. on the 20th time he chooses a card, what is the probability that andy will choose an ‘r’?

Explanation:

Step1: Identify total and favorable outcomes

Total number of cards is 8, number of 'R' cards is 2.

Step2: Calculate probability

Probability formula is $P=\frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}$. So $P = \frac{2}{8}=\frac{1}{4}$.
Since it's a replacement - based selection, each draw is an independent event and the probability remains the same for the 20th draw.

Answer:

$\frac{1}{4}$