Laboratory data show that the time required to complete two chemical reactions in a production process varies. The first reaction has a mean time of 40 minutes and a standard deviation of 2 minutes; the second has a mean time of 25 minutes and a standard deviation of 1 minute. The two reactions are run in sequence during production. There is a period of 5 minutes between the two reactions as the product of the first reaction is pumped into the vessel where the second reaction will take place.

a) What is the standard deviation of the combined process?

Question

Laboratory data show that the time required to complete two chemical reactions in a production process varies. The first reaction has a mean time of 40 minutes and a standard deviation of 2 minutes; the second has a mean time of 25 minutes and a standard deviation of 1 minute. The two reactions are run in sequence during production. There is a period of 5 minutes between the two reactions as the product of the first reaction is pumped into the vessel where the second reaction will take place.

a) What is the standard deviation of the combined process?

aihberkhan · Answer

Help with another? @Michele_Laino

aihberkhan · Answer

By the way I got 70 for the mean guys.

yuliacosta111 · Answer

number 2

michele_laino · Answer

I also think that we have to use the quadratic formula