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## Book Organization

In how many different orders can six books be organized in a shelf?

## Normal Distribution Percentages

In the normal distribution, what percentage of scores fall within one standard deviation of the mean?

## I Know Kung Fu

What is the ratio of the number of composite integers to the number of prime integers in the interval [1,10]?

## Describe the Data

Given the following data, which of the following terms best describes the data?

## Intelligent Doodles

A friend of yours draws a circle circumscribing a regular octagon. What is the ratio of the area of the octagon to the circle?

## Population Growth

Which of the following would be best to use for population growth with known upper limit?

## Effectiveness of Hand Wash

Bacteria such as V. cholerae are known to follow an exponential growth curve rate, and will double their number every 15 minutes. Fortunately, anti-bacterial hand wash can kill 99.9% of bacteria on a surface. If a colony of 500 V. cholerae cells are left alone for 2 hours, then anti-bacterial handwash is applied thoroughly, how many bacterial cells are left?

## Filling Cylinders

How many cubic centimeters of water will approximately be required to fill a cylinder with a 3 cm radius and 7 cm height?

## Predict Number of Lions

A researcher is attempting to predict the number of lions in an African habitat based on previous data. He has formed a regression equation which is: Y = 25 + 0.5X – 2ZX, where X is the number of years since the first population sample, and Z is the death rate of the lions. If it has been 10 years, and the death rate is 1 lion per year, what is the predicted number of lions in the habitat?