What is the probability that four coins all land on heads?

`1/4`

`2/4`

`1/2 xx 1/2 xx 1/2 xx 1/2`

`1/2 + 1/2 + 1/2 + 1/2`

What is the probability that out of three dice, none of them roll a 6?

`15/18`

`5/6 xx 5/6 xx 5/6`

`1 - (1/6 xx 1/6 xx 1/6)`

`1 - (5/6 xx 5/6 xx 5/6)`

A stack of cards has 3 blue cards, 4 red cards, and 5 purple cards. Which of these could be calculated as `(3/12 xx 9/11) + (4/12 xx 8/11) + (5/12 xx 7/11)`?

Two random cards are the same color.

Three random cards are the same color.

Two random cards are not the same color.

Three random cards are not the same color.

Which of these could be calculated as `1 - (39/52 xx 38/51 xx 37/50)` when drawing three cards?

All three cards are hearts.

None of the three cards is hearts.

At least one of the three cards is hearts.

At least one of the three cards is not hearts.