The function has the property for all real numbers.

The rule for could be

Which one of the following shows the graph of the inverse function of :

A random sample of students were sampled and asked about their preferred subject at school, Maths or Science. Two students said they prefer Maths. A confidence interval for the proportion of students in the population who prefer Maths is given by:

In a particular town, of the population said they would vote for the current Mayor. If a random sample of townspeople is taken, the probability that more than half of them will vote for the current Mayor is: 

The graph of a standard normal distribution with and is given below.

The graph of a normal distribution with and , plotted on the same scale, could be:

The discrete random variable  has a binomial distribution. The mean of is and the variance of is . The number, , of independent trials, and the probability, , of success in each trial are given by:

Which of the following graphs illustrate a binomial distribution where:

 and

The value of for which  forms a probability density function is: