A) x and y are two numbers taken from the list below. 5
6
7
8
9
10
(i) What values of x and y will make 3x – 2y equal zero? x = 6
y = 9
(ii) Work out the greatest possible value of 3x - 2y.
I
(iii) Work out the least possible value of 3x - 2y.
20
b) Find the value of 5(a - 4b) when a = -7 and b = 4

Since , you have



Since , you have



The empirical rule says that approximately 68% of a normal distribution falls within one standard deviation of the mean, you have



Finally, since those with IQ greater than 118 comprise half of the above percentage (due to the distribution's symmetry), you have