Word Problems Wks #1.notebook
August 15, 2012
Identifying Slope and Y­intercept from WP's
You rent a bike for $20 plus $2 per hour. An auto repair shop can charge $50 plus $25 per hour.
A candle is 6 inches tall and burns at a rate of 1/2 inch an hour.
The temperature is 15 degrees and is expected to fall 2 degrees each hour during the night.
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Word Problems Wks #1.notebook
August 15, 2012
1.) Scores on achievement test (a) are related linearly to scores on another test (b). Here are two students scores: a = 500, b = 100 and a=680, b= 127. Use the ordered pairs (a,b).
a.) Write a linear equation for these data points.
b.) Use this linear equation to predict the scores on the b test for a student with a score of 700 on the a test.
A school record in a certain race in 1980 was 3.8 minutes. In 2000 the school record was 3.65 minutes. Use the ordered pairs.
2.)
a.) Find a linear equation for these data points.
b.) What will the school record be in 2010?
3.) The total length of a certain species of snake is related linearly to the tail length of this snake. Here are the measurements for two snakes of this species. Snake 1: total length 150mm and tail length 19 mm. Snake 2: total length 300mm and tail length 40 mm. Use the ordered pairs.
a.) Find a linear equation for the data points.
b.) Use the linear equation to predict the tail length of a snake with a total length of 200 mm.
c.) Use the linear equation to predict the tail length of a snake with a total length of 350mm.
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Word Problems Wks #1.notebook
August 15, 2012
4.) As long as two of the same species of tree get the same water and sunlight, the diameter of the tree’s trunk will be linearly related to the age of the tree. One tree is 36 years old and has a diameter of 12 inches. The other tree is 9 years old and has a diameter of 3 inches. Use the ordered pairs.
a.) What is the rate of change for the two trees per year?
b.) Find the linear equation for the data points.
c.) Use the linear equation to find the diameter of a tree that is 198 years old.
5.) The cost of a taxi ride is linearly related to the length of miles traveled for the trip. A two mile trip costs $4.00. A twenty mile trip costs $31.00. Use the ordered pairs.
a.) Find a linear equation for the data points.
b.) What is the cost of a 100 mile trip?
c.) How many miles can I travel by taxi if I have $50.00?
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Word Problems Wks #1.notebook
August 15, 2012
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