Smelling Out the Enemy. Snakes deposit chemical trails as they travel through their habitats. These trails are often detected and recognized by lizards, which are potential prey. The ability to recognize their predators via tongue flicks can often mean life or death for lizards. Scientists from the University of Antwerp were interested in quantifying the responses of juveniles of the common lizard to natural predator cues to determine whether the behavior is learned or congenital. Seventeen juvenile common lizards were exposed to the chemical cues of the viper snake. Their responses, in number of tongue flicks per twenty minutes, are presented in the following

Find and interpret a 90%confidence interval for the mean number of tongue flicks per 20minutes for all juvenile common lizards. Assume a population standard deviation of 190.0.

Short Answer

Expert verified

Sample mean is 532.1765.

90% confidence interval ofμis(456.372,607.981)

Step by step solution

01

Given Information

The response of common lizards in number of flicks per20 minutes is given below:

Also, population standard deviation is190.

02

Determination of sample mean

It is given that

i=113xi=9047

Therefore, sample meanx¯=1n×i=1nxi=117×9047=532.1765

03

Determination of confidence interval

For 90%confidence interval of μ,

confidence level =90%=100×0.90%

1-α=0.90

α=0.10

Hence, confidence interval of μis

x¯-z0.05×σn,x¯+z0.05×σn

=532.1765-1.645×19017,532.1765+1.645×19017

=532,1765-75.8045,532,1765+75.8045

=456.372,607.9810

Therefore,90%confidence interval ofμis456.372,607.9810

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