1. The number of cars that called at a petrol station on some days of a month is as shown in the table.

   Days of the month (x)	3	5	8	12	15	19	22	26
   Number of cars (y)	143	95	112	110	104	86	78	69

   (a)  Represent this information on a scatter diagram.

   1. Draw the line of best fit to pass through the point (, ) where  is the mean of x and  is the mean of y.
   2. Use your diagram to estimate
   3. the day 80 cars called at the station;
   4. how many cars a petrol attendant at the station should expect on the 25th day.

The report stated that majority of the candidates attempted this question and they performed very well in it. They were able to obtain  as 13.75 and  as 99.625. Majority of them were also able to draw the line of best fit to pass through the point (13.75, 99.625). The day 80 cars called at the station was day 18 while 74 cars should be expected on the 25th day.