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Data Analysis The table shows the projected numbers \(N\) (in millions) of people living in the United States. (Source: U.S. Census Bureau) A model for the data is \(N=3.21 t+277.3\), where \(t\) represents time in years, with \(t=20\) corresponding to the year 2020 . According to the model, in what year will the population exceed 450 million?

Comparing Costs A cell phone company offers two text messaging plans. With the first plan, you can send an unlimited number of text messages for \(\$ 14\) per month. With the second plan, you can send 200 text messages for \(\$ 5\) and then pay \(\$ 0\). 15 for every additional message sent. How many text messages must be sent in a month for the first plan to be less expensive than the second plan?

Resizing a Picture You have an 8-by-10-inch photo of a soccer player that must be reduced to a size of \(1.6\) inches by 2 inches for the school newsletter. What percent does the photo need to be reduced to in order for it to fit in the allotted space?

Geometry The perimeter of a rectangle is 260 meters. The length is 30 meters greater than the width. Find the dimensions of the rectangle.

Geometry A circular target is attached to a rectangular board, as shown in the figure. The radius of the circle is \(4 \frac{1}{2}\) inches, and the measurements of the board are 12 inches by 15 inches. What percent of the board is covered by the target? (The area of a circle is \(A=\pi r^{2}\), where \(r\) is the radius of the circle.)

Writing Explain how to find the unit price of an item.

Summer Jobs During the summer, you work 30 hours per week at a gas station and earn \(\$ 8.75\) per hour. You also work as a landscaper for \(\$ 11.00\) an hour and can work as many hours as you want. You want to earn a total of \(\$ 400\) per week. How many hours must you work at the landscaping job?

Evaluate the expression. $$8-|-7+11|+(-4)$$

Writing When simplifying an algebraic expression involving fractions, why can't you simplify the expression by multiplying by the least common multiple of the denominators?

Solve the percent equation. 465 is what percent of 500 ?