# Mean and Standard Deviation of Time Required for a Chemical Reaction

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 fixed period of 5 minutes between them as the product of the first reaction is pumped into the vessel where the second reaction will take place.

a) What is the mean time required for the entire process?

b) Assuming the two reactions are independent, what is the standard deviation of the time required for the entire process?

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Denote by X the time required to complete the first reaction, and denote by Y the time required to complete the second reaction. Then the total time Z for the ...

#### Solution Summary

Solution gives all the steps to calculate the mean time and standard deviation of time required for a chemical reaction process in 103 words.