Question

0.5 0.5 1 mark) 4. A process control engineer wishes to estimate the true proportion of defective computer chips with width of the confidence interval no more than 0.18 and with probability 0.90. How many observations does the engineer need to include in the sample to achieve his goal?

Answer 1

Solution:-

4) The number of observation does the engineer need to include in the sample to achieve his goal is  21.

M.E = 0.18

C.L = 0.90
$\small M.E = z_{\alpha /2}\times\sqrt{ \frac{p(1-p)}{n}}$

MEp(1 -p) M.E

1.6452 0.18x0.50-0.50)

n = 20.87

n = 21