IB Math · Topic practice · IB Mathematics AA SL · Unit 4

Statistics & Probability

A mixed exercise set, like a textbook: every problem type this unit covers, shuffled together and getting harder as you go. Work on paper, reveal to check — and hit on any problem for the same kind with new numbers (198 in the pool).

Practice set — quiz with instant feedback and retries.Review the lessons for this unit first.

Exercises

12 of 198 shown

In a quiz, the scores $2, 3, 5, 8$ were obtained by $3, 5, 8, 4$ students respectively. Find the mean score.

Independent events $A$ and $B$ have $P(A) = \frac{1}{2}$ and $P(B) = \frac{1}{3}$ . Find $P(A \cap B)$ .

The ordered data set is $3,\ 5,\ 8,\ 12,\ 15,\ 19,\ 22,\ 26$ . Find the interquartile range.

Events $A$ and $B$ satisfy $P(A) = \frac{3}{10}$ , $P(B) = \frac{1}{5}$ and $P(A \cap B) = \frac{1}{10}$ . Find $P(A \cup B)$ .

In a class, $6$ girls play an instrument and $4$ do not; $5$ boys play and $6$ do not. A student is chosen at random. Given that the student is a girl, find the probability that she plays an instrument.

A biased coin lands heads with probability $\frac{1}{3}$ on each independent toss. It is tossed $4$ times. Find the probability of exactly $3$ heads.

In a quiz, the scores $3, 4, 6, 9$ were obtained by $1, 7, 9, 3$ students respectively. Find the mean score.

Independent events $A$ and $B$ have $P(A) = \frac{2}{3}$ and $P(B) = \frac{3}{10}$ . Find $P(A \cap B)$ .

The ordered data set is $10,\ 14,\ 20,\ 28,\ 34,\ 42,\ 48,\ 56$ . Find the interquartile range.

10.

Events $A$ and $B$ satisfy $P(A) = \frac{3}{5}$ , $P(B) = \frac{2}{5}$ and $P(A \cap B) = \frac{1}{5}$ . Find $P(A \cup B)$ .

11.

In a class, $6$ girls play an instrument and $5$ do not; $11$ boys play and $10$ do not. A student is chosen at random. Given that the student is a girl, find the probability that she plays an instrument.

12.

A biased coin lands heads with probability $\frac{2}{5}$ on each independent toss. It is tossed $5$ times. Find the probability of exactly $3$ heads.