General Mathematics Paper 2, WASSCE (PC), 2017

QUESTION 8
            

  1. The probabilities that Akafi and Iniola will pass an examination are  and  respectively. Find the probability that only Iniola will pass the examination.

 

  1.  

 

In the diagram, circle XYZ is inscribed in an equilateral triangle PQR. If O is the centre of the circle and |XY| = 10 cm, calculate, correct to the nearest whole number:

  1. XOY;
  2. Area of the major sector XZY. {Take π =

 

Observation

 

The report from the Chief Examiner stated that most Candidates’ avoided this question and those who attempted it only did well in part (a).
In part(a), they did as expected by finding pro(that only Iniola will pass) =  =  .
In part (b), they were expected to note that  and  are tangents to the circle at X and Y and as such . Also,  is an equilateral triangle. Then, . Furthermore, , so that , then  .

In part (bii), from , the radius of the circle is  then, r = 5.7735 cm.
The value of  so that Area =
Area = 70 cm2