Question

Greg has four different colored cards in a box. Yellow, red, blue, and green. He randomly selects one card, records the color, and then replaces the card into the box. If Greg does this 300 times, how many yellow cards should he expect to select?

Answer 1

He should expect to select 75 yellow cards.

Explanation:

Since there is replacement, for each trial, we have:

1 yellow card

1 red card

1 blue card

1 green card.

If Greg does this 300 times, how many yellow cards should he expect to select?

Each trial, there are 4 cards, one of which is yellow. So 1/4 = 0.25 probability of selecting a yellow card.

Over 300 trials

0.25*300 = 75

He should expect to select 75 yellow cards.