A student is assigned a 3000–word paper for a class. He types 120 words in 4 minutes. At this rate how long will it take him to complete the paper?

A spring with a 75 g weight attached stretches 20 cm. How much weight is required to stretch the spring 144 cm?

(Hint: the increase in length varies directly with the weight)

Mr. S works as a waiter in a restaurant. He earns $1200 per month as a base salary, plus tips averaging 20% of the meals he serves. Write a linear model for the situation, and use it to find the amount earned if Mr. S serves meals worth a total of $4000.

In American Football, a field goal earns 3 points and a touchdown (with extra point) earns 7. Assuming a team scores only in these two ways, and earns a total of 48 points, write an equation relating the number of field goals x with the number of touchdowns y. Put the equation in slope–intercept form, and graph it.

The following table shows the number of CDs in Arun's music collection over the years.

Make a scatter plot of this data. Write a linear model. What does the slope represent? Estimate the number of CDs Arun will have in 2010.

Suppose you spend $30.00 on snacks for a party. The dried shrimp cakes cost $3.00 per pound and the chocolate–covered mushroom stems cost $4.50 per pound. Write an equation in standard form that represents the different amounts (in pounds) of shrimp cakes, S, and mushroom stems, M, you could buy.

If you buy 2 pounds of mushroom stems, how many pounds of shrimp cakes can you buy?

There is a population of 200 tigers in a national park. They are being illegally poached at the rate of 8 per year. Assume the population is otherwise unchanging, and write a linear model and graph it. What does the x–intercept signify?

The perimeter of a fenced rectangular area is 75 m. Write a linear model relating the length and width. If the length is 5 m, find the width.