## askme12345 Group Title STATISTICS 2 years ago 2 years ago

1. A physician wanted to estimate the mean length of time that a patient had to wait to see him after arriving at the office. A random sample of 36 patients showed a mean waiting time of 23.4 minutes and a standard deviation of 7.2 minutes. Find a 96% confidence interval for .

2. amistre64

sd/sqrt(n) sounds familiar

3. amistre64

$z=\frac{x-mean}{sd/\sqrt{n}}$

4. amistre64

where z is the value at Za = .02 maybe?

5. amistre64

|dw:1327284026014:dw|

6. amistre64

i know im missing something :/

7. amistre64

we want the interval of Lx to Rx right?

8. amistre64

z = 2.06 if i see the table right

9. amistre64

$z=\frac{x-mean}{sd/\sqrt{n}}$ $z(sd/\sqrt{n})={x-mean}$ $z(sd/\sqrt{n})+mean={x}$ $2.06(7.2/\sqrt{36})+23.4={x}\text{ to the right}$ $-2.06(7.2/\sqrt{36})+23.4={x}\text{ to the left}$

10. amistre64

with any luck that is :) im sure im forgetting something important tho