Suppose the amount of heating oil used annually by households in Ontario is normally distributed, with a mean of 760 litres per household per year and a standard deviation of 150 litres of heating oil per household per year.
a. What is the probability that a randomly selected Ontario household uses more than 570 litres of heating oil per year?
b. What is the probability that a randomly selected Ontario household uses between 680 and 1130 litres per year?
c. If the members of a particular household were scared into using fuel conservation measures by newspaper accounts of the probable price of heating oil next year, and they decided they wanted to use less oil than 97.5% of all other Ontario households currently using heating oil, what is the maximum amount of oil they can use and still accomplish their conservation objective?

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The Answer of Suppose the amount of heating oil used annually by households in Ontario is normally distributed, with a mean of 760 litres per household per year and a standard deviation of 150 litres of heating oil per household per year.
a. What is the probability that a randomly selected Ontario household uses more than 570 litres of heating oil per year?
b. What is the probability that a randomly selected Ontario household uses between 680 and 1130 litres per year?
c. If the members of a particular household were scared into using fuel conservation measures by newspaper accounts of the probable price of heating oil next year, and they decided they wanted to use less oil than 97.5% of all other Ontario households currently using heating oil, what is the maximum amount of oil they can use and still accomplish their conservation objective?

Suppose the Amount of Heating Oil Used Annually by Households