91Ó°ÊÓ

Anthropologists and forensic scientists classify skulls using $$\frac{L+60 W}{L}-\frac{L-40 W}{L}$$ where \(L\) is the skull's length and \(W\) is its width a. Express the classification as a single rational expression. b. If the value of the rational expression in part (a) is less than \(75,\) a skull is classified as long. A medium skull has a value between 75 and \(80,\) and a round skull has a value over \(80 .\) Use your rational expression from part (a) to classify a skull that is 5 inches wide and 6 inches long.

Write each number in decimal notation. $$ 4.63 \times 10^{-5} $$

Are first putting on your left shoe and then putting on your right shoe commutative?

In Exercises \(77-84,\) evaluate each expression without using a calculator. $$36^{1 / 2}$$

Write each number in scientific notation. $$ 0.014 $$

Write each number in scientific notation. $$ 0.000972 $$

The polynomial \(104.5 x^{2}-1501.5 x+6016\) describes the death rate per year, per \(100,000\) men, for men averaging \(x\) hours of sleep each night. Evaluate the polynomial for \(x=10 .\) Describe what the answer means in practical terms.

If you are given two real numbers, explain how to determine which one is the lesser.

Which one of the following statements is true? a. Every rational number is an integer. b. Some whole numbers are not integers. c. Some rational numbers are not positive. d. Irrational numbers cannot be negative.

In Exercises \(85-94,\) simplify using properties of exponents. $$\frac{\left(2 y^{1 / 5}\right)^{4}}{y^{3 / 10}}$$