## Introductory Statistics 9th Edition

Using the $z$ values in the tables, we find: N=500, p=.05 , q= .95, μ=np =500*.05=25, σ = $\sqrt npq$=$\sqrt 500*.05*.95$=4.8734 a. $P(x=29)$ =$P(28.5\leq x \leq 29.5)$ For x=28.5, z = $\frac{28.5-25}{4.8734}$=0.7182 For x=29.5, z = $\frac{29.5-25}{4.8734}$=0.9234 $P(28.5 \leq x \leq 29.5)$= $P(0.7182\leq z \leq -0.9234)$ =0.8221-0.7637= 0.0457 b. $P(x \geq 27)$ $P(x \geq 27)$ : z = $\frac{27-25}{4.8734}$ =0.4104 $P(z \geq 0.4104)$ =0.3408 c. $P(15\leq x \leq 22)$ For x=15, z = $\frac{15-25}{4.8734}$=-2.0520 For x=22, z =$\frac{22-25}{4.8734}$=-0.6156 $P(15 \leq x \leq 22 )$ = $P(-2.052\leq z \leq -0.6156)$ =0.2691-0.0201= 0.249