Rose Harrison and Clara Huizink Solutions for Exercise 12: Practice 4

There are $9$ numbered cards on a table, each with a number $1$ to $9$ printed on one side. The other side is blank. The cards are all blank side up. Serena picks two cards from the set.

Find the probability that both cards are even.

There are 9 numbered cards on a table, each with a number $1$ to $9$ printed on one side. The other side is blank. The cards are all blank side up. Serena picks two cards from the set.

Find the probability that at least one card is odd. 

Of a group of five students, two will be selected for a school trip by picking names out of a hat. The five students are Jack, Mary, Rafa, Harry and Pietronella.

With the aid of a tree diagram or a table of outcomes, find the number of different possible combinations of students that could be selected.

Of a group of five students, two will be selected for a school trip by picking names out of a hat. The five students are Jack, Mary, Rafa, Harry and Pietronella.

Find the probability that Mary and Pietronella will go on the trip.

Alix has a box of red, yellow and green marbles. She picks a marble from the box, without looking.
The table shows the probabilities of picking the different colors.

$\begin{array}{|cc|}\hline \text{ Color }& \text{ Probability }\\ \text{ red }& 0.4\\ \text{ yellow }& 0.25\\ \text{ green }& \\ \hline\end{array}$

What is the probability that Alix picks a green marble? 

Alix has a box of red, yellow and green marbles. She picks a marble from the box, without looking.
The table shows the probabilities of picking the different colors.

$\begin{array}{|cc|}\hline \text{ Color }& \text{ Probability }\\ \text{ red }& 0.4\\ \text{ yellow }& 0.25\\ \text{ green }& \\ \hline\end{array}$

There are $5$ yellow marbles in the box. How many red marbles are there?

Alix has a box of red, yellow and green marbles. She picks a marble from the box, without looking.
The table shows the probabilities of picking the different colors.

$\begin{array}{|cc|}\hline \text{ Color }& \text{ Probability }\\ \text{ red }& 0.4\\ \text{ yellow }& 0.25\\ \text{ green }& \\ \hline\end{array}$

Alix picks a marble, then replaces it in the box and picks another.

Draw a tree diagram to show the probabilities.

Alix has a box of red, yellow and green marbles. She picks a marble from the box, without looking.
The table shows the probabilities of picking the different colors.

$\begin{array}{|cc|}\hline \text{ Color }& \text{ Probability }\\ \text{ red }& 0.4\\ \text{ yellow }& 0.25\\ \text{ green }& \\ \hline\end{array}$

Alix picks a marble, then replaces it in the box and picks another.

What is the probability that at least one of the marbles is red?