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(Choose 1 answer)
(See picture)
A. We use Z_test in this situation.
B. This is a 1-sided test
C. The stat value is 2.52
D. This is a 2 sided test.
A product developer is interested in reducing the drying time of a primer paint.Two formulations of the paint are tested; formulation 1 is the standard chemistry,and formulation 2 has a new drying ingredient that should reduce the drying time. From experience, it is known that the standard deviation of drying time is 8 minutes, and this inherent variability should be unaffected by the addition of the new ingredient.
Ten specimens are painted with formulation 1, and another 10 specimens are painted with formulation 2; the 20 specimens are painted in random order.
Two sample average drying times (minutes) are x₁ = 121; x2 = 112.
Choose the FALSE statement.
