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?

He should expect to select 75 yellow cards.

Step-by-step 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.

faster, im not sure why but i know it is faster

the height of the surface increases from the center out to the sides of the road.

step-by-step explanation:

as we move out we move away from the x-axis.

and as mentioned in the problem statement that height of a road increases when we move away from the center x.

hence proved that 3rd option

the height of the surface increases from the center out to the sides of the road.

is the correct option.