Question

A deck of 10 cards labeled 1–10 is shuffled. One card is selected at random. If the experiment is repeated 120 times, how many times will you expect to select number 5?(1 point)
Responses

1120
Start Fraction 1 over 120 End Fraction

10
10

110
Start Fraction 1 over 10 End Fraction

12
12

1 answer

To find the expected number of times you would select the number 5 from a deck of 10 cards labeled 1 to 10 over 120 trials, you can use the concept of probability.

The probability of selecting the number 5 in one draw is:

\[ P(5) = \frac{1 \text{ (the number 5)}}{10 \text{ (total number of cards)}} = \frac{1}{10} \]

If you repeat this experiment 120 times, the expected number of times to select the number 5 is:

\[ \text{Expected number of times} = P(5) \times \text{Number of trials} = \frac{1}{10} \times 120 = 12 \]

Thus, the expected number of times to select the number 5 is 12.

The correct response is: 12