Question

The sample mean weights for two varieties of lettuce grown for 16 days in a controlled...

The sample mean weights for two varieties of lettuce grown for 16 days in a controlled environment are 3.259 and 1.413 and the corresponding sample standard deviations are .400 and .220. If the sample sizes for the two varieties are 9 and 6 respectively, calculate the pooled sample standard deviation:

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Answer #1

Solution

Given ,

  =3.259 , = 1.413

s1 = 0.400 , s2 = 0.220

n1 = 9 , n2 = 6

Let denotes the pooled variance and denotes the pooled standard deviation.

=

=   

=  

=  0.34216505239

Answer : The pooled sample standard deviation: 0.34216505239

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