The table gives the distribution of marks obtained by a number of pupils in a class test. 

The bar chart show the statistics of the number of passes in an examination in a school from 2001 to 2004. What is the ratio of the total number of passes to the total number of failures

The average age of a group of 25 girls is 10 years. If one girl aged 12 years and 4 months joins the group, find, correct to one decimal place, the new average age of the group.

A stationary boat is observed from a height of 100 m . If the horizontal distance between the observer and the boat is 80 m. Calculate, correct to two decimal places, the angle of depression of the boat from the point of observation

Given that$\cos {{30}^{\circ }}=\sin {{60}^{\circ }}=\frac{\sqrt{3}}{2}$ and $\sin {{30}^{\circ }}=\cos {{60}^{\circ }}=\frac{1}{2}$ evaluate $\frac{\tan {{60}^{\circ }}-1}{1-\tan {{30}^{\circ }}}$ 

A bearing of 320^o expressed as a compass bearing is

If P(2, 3) and Q( 2, 5) are points on a graph, calculate the length PQ

Calculate the gradient (slope) of the line joining points (–1, 1) and (2, –2) 

In the diagram PQ and PS are tangents to the circ centre O. If $\angle PSQ=m$, $\angle SPQ=n$ and $\angle SQR={{33}^{\circ }}$.

Find the value of (m + n)

The diagram show a circle centre O, If $\angle ZYW={{33}^{\circ }}$ Find $\angle ZWX$