Astress analysis was conducted on random samples of epoxy-bonded joints from two species of wood. a random sample of 120 joints from species a had a mean shear stress of 1250 psi and a standard deviation of 350 psi, and a random sample of 90 joints from species b had a mean shear stress of1400 psi and a standard deviation of 250 psi. find a 98% confidence interval for the difference in mean shear stress between the two species

Our required 98% confidence interval would be (53.51,246.49).

Step-by-step explanation:

Since we have given that

Sample of joints from species A = 120

Mean of shear stress = 1250 psi

Standard deviation = 350 psi

Sample of joints from species B = 90

Mean = 1400 psi

Standard deviation = 250 psi

98% confidence interval

α = 100 -98  = 2%

98% confidence interval would be

Hence, our required 98% confidence interval would be (53.51,246.49).

answer: group b.

step-by-step explanation: