Use what you just learned about negative slopes to solve this problem. A storm moves at a rate of 8 miles per hour. It is 200 miles away from Freeport and headed directly for this town. The equation y = 200 - 8x can be used to represent this function. Identify the slope and y-intercept and explain what they represent.

Question
Linear equations and graphs
asked 2020-12-28
Use what you just learned about negative slopes to solve this problem. A storm moves at a rate of 8 miles per hour. It is 200 miles away from Freeport and headed directly for this town. The equation y = 200 - 8x can be used to represent this function. Identify the slope and y-intercept and explain what they represent.

Answers (1)

2020-12-29
Write the function in slope-intercept form y = mx + & where m is the slope and is the y-intercept: y=-8x+200 So, the slope is —8 and the y-intercept is 200. The slope represents the rate of the storm which is 8 miles per hour. The negative sign indicates that the distance between Freeport and the storm is decreasing. The y-intercept represents the initial distance of the storm and the town. This also represents the distance between Freeport and the town.
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The table below shows the number of people for three different race groups who were shot by police that were either armed or unarmed. These values are very close to the exact numbers. They have been changed slightly for each student to get a unique problem.
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White - 1176
Hispanic - 378
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Suspect was unarmed:
Black - 60
White - 67
Hispanic - 38
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White - 1243
Hispanic - 416
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Give your answer as a decimal to at least three decimal places.
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b) What percent are Unarmed?
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This just means that the percentage of times that both things happen equals the individual percentages multiplied together (Only if they are Independent of each other).
Therefore, if a person's race is independent of whether they were killed being unarmed then the percentage of black people that are killed while being unarmed should equal the percentage of blacks times the percentage of Unarmed. Let's check this. Multiply your answer to part a (percentage of blacks) by your answer to part b (percentage of unarmed).
Remember, the previous answer is only correct if the variables are Independent.
d) Now let's get the real percent that are Black and Unarmed by using the table?
If answer c is "significantly different" than answer d, then that means that there could be a different percentage of unarmed people being shot based on race. We will check this out later in the course.
Let's compare the percentage of unarmed shot for each race.
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Think of it this way. If you went to a college that was 90% female and 10% male, then females would most likely have the highest percentage of A grades. They would also most likely have the highest percentage of B, C, D and F grades
The correct way to compare is "conditional probability". Conditional probability is getting the probability of something happening, given we are dealing with just the people in a particular group.
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