A. Find Linda s z-score. Round to the nearest 100 th. z =

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1 1. Translate and solve: Eight less than twice a number is six. 2x 8 = 6 2x = 14 x = 7 2. Evaluate (5 x 2 9) 4(y 2x) if x = 3 and y = 6. ( ) 4(6 2 3) (5 6 9) 4(6 6) 8 4(12) 2(12) 3. Solve: Multiply both sides by the reciprocal x = What is the range of the equation y = 6x 2 if the domain is {-2, 3, 5}? y = 6(-2) 2 = = -14 R :{-14, 16, 28} y = 6(3) 2 = 18 2 = 16 y = 6(5) 2 = 30 2 = Find the slope of the line that passes through the points (5, 6) and (26, -1). m = 6. Linda is on a swim team. Her best 50 freestyle time is seconds. The team average is seconds. The team s standard deviation is 1.2 seconds. A. Find Linda s z-score. Round to the nearest 100 th. z = B. What does Linda s z-score tell you about her time? Linda s time is very far below the mean. In other words, she s a fast swimmer!

2 1. Translate: Two times the sum of a number and four is equivalent to seven less than the square of the same number. 2(x 4) = x Simplify: 10x 4(2x 6y) 2y 10x 8x 24y 2y 2x 26y 3. Solve: 29 2y 8 = 5y 7-7y = -28 y = 4 4. What is the domain and range of the function shown in the graph at the right? D:{ } and R: {} 5. Find the root of the function f(x) = Reminder: root is where the graph crosses the x axis (so where y = 0!} 0 = x = -12 x = Jeff brought his family to the fair and paid $20 for a family admission pass. During the tractor pull, he bought all of his kids an elephant ear for $6.75 each. Write and solve an equation that represents how many kids Jeff has if he spent a total of $ Equation: 6.75x 20 = x = x = 5 kids

3 1. What is the slope of the line represented by the equation -5y 15 = 4x? -5y = 4x 15 so slope = y = 2. Solve for x: 12x 8 > 2x x > - 30 x > Solve -4 < -2x Graph your solution. -14 < -2x < > x > 5 so 5 < x < 7 4. Use the graph at the right to identify the following: Slope: - Roots: x = 2 x-intercept: x = 2 or (2, 0) y-intercept: y = 5 or (0, 5) Equation of the line: y = 5. Let f(x) = 4x 5 and g(x) = 2x 2 5x 8. Find g(f(-3)). f(-3) = 4(-3) 5 = = - 7 g(-7) = 2(-7) 2 5(-7) 8= 2(49) 35 8 = = 141 g(f(-3) = Tonya wants to know how long her shadow is. She knows that her mailbox is 3.5 feet tall and has a shadow that is 1.4 feet long. If Tonya is 6 feet tall, how long is her shadow? Round to the nearest 10 th.!"#$!% &!'()* 3.5x = 8.4 so x = 2.4 feet

4 1. Solve:, 2. Solve: -./ 12x 48 = 9x 12 18x 12 5 = 18x 7 3x = 60 18x 17 = 18x 7 x = 20 0 = - 24 No Solution For questions 3 and 4: A group of students were asked how many pages they could read in one hour. The mean number of pages was 80 and the standard deviation was Find the mean absolute deviation for this group of students. Subtract each data point from the mean. Then, take the average of that new list of numbers. 30, 1, 5, 34, 20 MAD = 18 Student # of Pages Ken 50 Becca 79 Shannon 85 Heidi 114 Joel Which of these students is an outlier? Use z-scores to explain how you know. Heidi is an outlier because her z-score is 3.09 and all outliers have a z-score of above 3 or below Five students were asked how many pull-ups they could complete. The responses were 7, 9, 15, 10, and 13. This means that the mean number of pull-ups was If a sixth student were to say that he could only complete 1 pull-up, would it increase or decrease the group s mean? Would it increase or decrease the groups standard deviation? Explain your reasoning. The mean would decrease b/c it is lower than the current data. The standard deviation would increase b/c 1 is farther away from the mean than all of the other data making the spread of the data greater. If the spread is greater, the standard deviation is greater. 6. Draw a graph that is NOT function. Then, generate a list of ordered pairs that does NOT represent a function. Explain how you know that both of these examples are not functions. In both cases, these are not functions because the x-values repeat. In the case of the graph, it fails the vertical line test (a vertical line would intersect the graph more than once.) x y

5 1. Solve for z: x = 0 3x = yz Write the equation for the line with a slope of that contains the point (4, -2) in standard form. y - -2 = y 2 = 4( y = -3x 4y = Find the slope of line graphed at the right. Then, write an equation for the line. m = 0 y = 2 4. The mean of a data set is The standard deviation is 6.2. What value is two standard deviations above the mean? (6.2) = = Justify each of the steps written in the table below. Steps Justification 115 = 5y. Let y = x 12. Given 115 = 5(x 12) Substitution Property 115 = 5x 60 Distributive Property 55 = 5x Subtraction Property of Equality Multiplication Property of Equality 11 = 1x Multiplicative Inverse 11 = x Multiplicative Identity x = 11 Symmetric Property