Finding the confidence interval at either 90%, 95% or 99% for the mean given the mean of a sample. The population variance is given and so the z values are used. Various scenarios are included.

Finding the confidence interval at either 90%, 95% or 99% for the mean given the mean of a sample. The population variance is given and so the z values are used. Various scenarios are included.

Students are given a decimal in the form 0.X and asked to identify its value, either X units, X tenths, X hundredths or X tens.

The student must write R code to assign the given value to the variable x.

Given a randomly-generated list, the student must write code to return its first value.

There's an alternative to check if they get the second item, which they might do if they don't realise Python lists are zero-indexed.

Students are asked to move an x-axis slider representing standard deviation on a normal distribution to make the area between (mean - slider value) and (mean + slider value) equal to a certain percentage. The 3 possible percentages correspond to the mean plus or minus 1, 2 or 3 standard deviations.

Friction

All the answers in this question are equations. In order to mark each equation, Numbas needs to pick some values that satisfy the equation and some that don't, and check that the student's answer agrees with the expected answer.

Any equation with the same solution set as the expected answer will be marked correct.

The answer to this question is a differential equation involving $y''$, $y'$ and $y$.

A variable value generator for $y$ ensures that the right values are tested to check that the student's answer is equivalent to the expected equation.

Finding the confidence interval at either 90%, 95% or 99% for the mean given the mean of a sample. The population variance is given and so the z values are used. Various scenarios are included.

Calculating the nutritional values of cereal as percentages of servings and RDAs

Calculating the original amount when told that $p\%$ is $x$. The value given can be non-integer.

Calculating the original amount when told that $p\%$ is $x$. The value given and the original values are both integers.

Students are shown a normal distribution, and a slider that moves the distribution horizontally. They are asked to move it so that the mean is equal to a particular value.

Reading a value from a stacked bar chart.

Reading a value from a simple bar chart.

One number as a percentage of another.  Biology context. Includes standard form.
Realistic values.

Stating orders of magnitude for real-world values, e.g. height of Everest, diameter of a atom.

Reading values from a Venn diagram, required unison, intersection and complement.

Given a regular n-gon, students are asked for the sum of external angles, sum of internal angles, and the values of the external and internal angles.

Given n-1 angles inside a polygon, students have to calculate the value of the last internal angle.

Students explore the relationship between length and area of a rectangle.

The perimeter of the rectangle is randomised. Students are given 11 different lengths, and asked to compute rectangle width and area for each. They are then asked to graph the function, identify it as a parabola, and estimate the maximum value.

Students are shown one of 5 different radial surveys and asked to answer one of 8 questions about it.

2 questions ask for the length of a side.

2 questions ask for the value of an angle.

2 questions ask for the area of a triangle.

1 question asks for the land area, and 1 question asks for the land perimeter.

The values are hard coded. In cases where your choice of precision affects your answer, a range of answers is accepted, and a comment is made in the advice to that effect.

Students are shown a random bearing and given its value as a compass bearing.

They are asked to give its value as a true bearing.

Student is given a triangle with the value of 2 sides and 1 or 2 angles and asked to find the value of the third side using the cosine rule. Triangle can be acute or obtuse.

Side and angle lengths are randomised. Units are randomised.

Student is given a triangle with the value of 3 sides and asked to find the value of an angle. Triangle can be acute or obtuse.

Side and angle lengths are randomised. Units are randomised.

Student is given a triangle with the value of 1 side and 2 or 3 angles and asked to find the value of another side. Triangle can be acute or obtuse.

Side and angle lengths are randomised. Units are randomised.

Student is given a triangle with 2 or 3 side lengths given and asked to use the sine rule to find the value of an angle. Triangle can be acute or obtuse.

Side and angle lengths are randomised. Units are randomised.

Students are shown a right angled triangle and asked to find the value of an angle using a trig identity.

The triangle is a fixed image, but the angles and side lengths are randomly selected.

The angle is to be given in degrees and minutes.

There are 4 orientations of the triangle in the diagram. The orientation is randomly chosen.