Question

A manufacturer of electrical components wants to choose between two types of plastic suitable for their manufacture, the characteristic considered as an important parameter is the breaking stress of the plastic. If you have investigated with two samples one the first of size 10 and the second of 12, whose averages are 162.5 and 155.0 respectively and with standard deviation equal σ₁= σ₂ = 1.0psi. The company will not adopt the plastic of sample 1 unless the rupture stress of this exceeds that of sample 2. Based on this information, should the company use plastic 1? Use a 5% level of significance to make a decision.

Please provide a step by step solution. Working must be done by HAND.

Answer 1

As per my knowledge something is missing in the following line of the question:-

The company will not adopt the plastic of sample 1 unless the rupture stress of this exceeds that of sample 2.

However I have provided the solution according to given situation.