Find the value of the standardized z-test statistic and the area above 140 for a n(160,25) distribution. round your answer to three decimal places. a) z = - 0.8, area = 0.212b) z = -0.8, area = 0.788 c) z = 0.8, area = 0.212 d) z = 0.8, area = 0.788

B

Step-by-step explanation:

standard z-test statistic=x-mean/standard deviation

N(160,25)⇒N(mean,standard deviation)

mean=160

standard deviation=25

x=140

z=140-160/25=-20/25=-0.8

area above 140=P(z>0.8)=P(-0.8<z<0)+P(0<z<∞)=0.2881+0.5=0.7881

so z=-0.8, area=0.7881

each side has a different length.  

step-by-step explanation: