According to records of commonwealth edison, monthly electric consumption for january follows a normal distribution with a mean of 1,650 kilowatt hours, and a standard deviation of 320 kilowatt hours. commonwealth edison wants to identify its heaviest users, which are those that are in the top 6% of electric consumption. how many kilowatt hours in january would qualify for the heavy user classification?

Explanation:

Since the monthly electric consumption for January follows a normal distribution, you must use a standard normal table (Z table), which provides the probabilities for the (normalized) Z-scores.

The top 6% of electric consumption, means that you must find the z-score for which the probablitiy is ≥ 0.06.

The corresponding z-score shown in the table is 1.555.

Now just use the equation:

Where:

Substituting:

which piece of furniture will have the most inertia and give the furniture movers the most difficulty in moving?  

answer

a 75kg dining table