A diver begins at sea level and descends vertically at a rate of \(2\frac{1}{2}\) feet per second. How long does the diver take to reach -15.6 feet?

Analyze Relationships

In Exercise 16, what is the relationship between the rate at which the diver descends, the elevation he reaches, and the time it takes to reach that elevation?

Check for Reasonableness

Jane withdrew money from her savings account in each of 5 months. The average amount she withdrew per month was $45.50. How much did she withdraw in all during the 5 months? Show that your answer is reasonable.

Justify Reasoning

Consider the two problems below. Which values in the problems are represented by negative numbers? Explain why.

(1) A diver below sea level ascends 25 feet to a reef at -35.5 feet. What was the elevation of the diver before she ascended to the reef?

(2) A plane descends 1.5 miles to an elevation of 3.75 miles. What was the elevation of the plane before its descent?

Analyze Relationships

How is solving -4x = -4.8 different from solving \(-\frac{1}{4}\text{x}\) = -4.8? How are the solutions related?

Communicate Mathematical Ideas

Flynn opens a savings account. In one 3-month period, he makes deposits of $75.50 and $55.25. He makes withdrawals of $25.15 and $18.65. His balance at the end of the 3-month period is $210.85. Explain how you can find his initial deposit amount.