8th grade practice test - divisional stem competition · 8th grade practice test - divisional stem...

TAME Divisional STEM Competition 8h Grade Practice Test

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8th Grade Practice Test - Divisional STEM Competition

Answer the following questions by marking the BEST answer on the answer sheet.

1. Mr. Gibbs, a teacher in the middle school, will eliminate each student’s lowest quiz grade when he computes

grades at the end of the semester. How will the procedure affect the mean and median for an individual

student whose grades are 95, 90, 85, and 58?

a. It will affect the mean more than the median.

b. It will affect the median more than the mean.

c. It will affect the mean and median equally.

d. It will have no effect on either the mean or the median.

2. Shannon needs to wrap a gift in the shape of a cube that has a side length of 1.5 ft. What is the least amount

of paper she needs to cover the gift?

a. 16.8 ft2 b. 13.5 ft2 c. 8.45 ft2 d. 3.375 ft2

3. The table to the right shows the population of Texas from 1900 to 2000.

Which of the following is true, based on the data above?

a. The population of Texas doubled from 1980 to 2000.

b. The population of Texas in 1990 was 4 times the population in 1920.

c. The population of Texas more than tripled from 1900 to 1960.

d. The population of Texas in 1980 was 2 times the population in 1950.

4. Jaine used three straws of different lengths to create triangles. Which statement is true about the triangle she

created with side lengths 5, 6, and 10?

a. It is a right triangle because the hypotenuse is shorter than the sum of the other 2 sides.

b. It is a right triangle because a² + b² = c²

c. It is a right triangle because it proportional to a 3, 4, 5 triangle.

d. It is a not a right triangle because a² + b² ≠ c²

5. Which answer gives the correct side lengths to the triangle to the right?

a. 2,2,4

b. √2, √2, 2

c. √1, √1, 2

d. 4,4,8

Copyright Texas Alliance for Minorities in Engineering (TAME) 01.19.2017


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6. What is the relationship between the volume of the cone and the volume of the cylinder as shown below?

a. The volume of the cone is 1/3 of the volume of the cylinder.

b. The volume of the cone is 1/2 of the volume of the cylinder.

c. The volume of the cone is 2/3 of the volume of the cylinder.

d. The volume of the cone is 4/3 of the volume of the cylinder.

7. The Squeaky Clean Car Wash charges by the minute, as shown by the chart below. Explain how you know

the relationship is linear.

Squeaky Clean Car Wash Charges

Time (min) 5 10 15 20 25

Charge $8 $13 $18 $23 $28

a. The charge decreases by a set amount as the time increases.

b. Both the charge and time increase by 8.

c. As the time increases by a set amount, the charge also increases by a set amount.

d. None of the above

8. From which equation could the chart below be created?

a. y = 4(x - 7) + 6 b. y = -3x – 8 c. y = x(3x + 2³) d. y = 4 - 3x

x -3 -1 3

y 3 -5 51

9. At a water park, the daily profit from the concession stands depends on the number of park visitors. The

equation p= 2.50v – 500 gives the estimated profit p in dollars when v people visit the park. For what number

of visitors will the profit be about $2,000?

a. 200 b. 400 c. 600 d. 1000

10. Which rule describes a translation of the original figure?

I. (x,y) (x + 2, y -3)

II. (x,y) (2x, y)

III. (x,y) (x + 1, 3y)

IV. (x,y) (x -2, y + 1)

a. II and III b. I only c. I and IV d. All of the above

11. One property of most alkali metals is that they are ________.

a. not very useful elements.

b. too hard to cut with a knife.

c. very reactive with other elements.

d. found in nature uncombined with other elements.



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12. Which of the following models represents the correct number of valence electrons in an argon atom? You

may use a periodic table to solve this problem.

a b c d

13. Which of the following is the LEAST likely to react?

a. an atom with 2 valence electrons

b. an atom with 4 valence electrons

c. an atom with 7 valence electrons

d. an atom with 8 valence electrons

14. Which is an example of the use of activation energy?

a. plugging in an iron

b. playing basketball

c. holding a lit match to paper

d. eating

15. When reactant particles collide more often, ________.

a. the reaction rate remains the same

b. the reaction rate decreases

c. the reaction rate increases


16. Which of the following is the formula for sodium fluoride?

a. SF b. SFl c. NaF d. NaFl

17. Below are diagrams of sound waves moving from one room into another through a door. Each sound wave

moves from left to right. Diagram B best illustrates that ____ when you are in the next room.

a. high pitches are easier to hear

b. high pitches are harder to hear

c. low pitches are harder to hear

d. low pitches are easier to hear

18. The rumbling sound of thunder is heard when lightning strikes far away because ________.

a. thunder has only high frequencies.

b. thunder has only low frequencies.

c. only high-frequency waves can diffract around trees, buildings, hills, and other barriers.

d. only low-frequency waves can diffract around trees, buildings, hills, and other barriers.



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19. Watson and Crick ________.

a. collected peppered moths to study their coloring.

b. took X-ray pictures of DNA.

c. made models to find out DNA's shape.

d. bred pea plants to study the patterns of heredity.

20. A symbiotic relationship in which one organism benefits and the other is unaffected is called ________.

a. parasitism b. commensalism c. mutualism d. organism

21. Which value below is not true for the inequality -4x + 5 ≤ 13?

a. -2 b. -4 c. 2 d. 4

22. Choose the correct statement to describe the correlation in the

graph?

a. It represents a positive correlation.

b. There is no correlation because it does not start at the origin.

c. It represents a negative correlation.

d. There is no correlation due to the outliers.

23. A hexagon has two sides with lengths 2x +1, two sides with lengths 3x -2, and two sides with lengths 4x -5.

Express the perimeter of the hexagon in terms of x.

a. 18x -12

b. 9x -6

c. 18x3 + 10

d. 18x -16

24. Evaluate 3𝑥−𝑦

3(𝑥−𝑦) if x = 5 and y = 3.

a. 0 b. 2 c. 3 d. 6

25. Simplify 12(1

4𝑥 +

1

3) −

1

2(12𝑥 − 6).

a. -3x + 7 b. 3x + 7 c. 4 d. -5x + 3

26. Solve 3w – 13 = 1

4(52 – 12w).

a. 41

3 b. -1 c. no solution d. all real numbers



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27. Nick worked 16 hours last week. He earned $5 per hour at a local restaurant and $5.50 per hour at a grocery

store. If he earned a total of $82, how many hours did he work at the grocery store?

a. 8 h b. 4 h c. 12 h d. 2 h

28. Solve for y in the equation 𝑥𝑦+𝑧

2 = a.

a.𝑦 = 2𝑎+ 𝑧

𝑥 b. 𝑦 =

2𝑎− 𝑧

𝑥 c. 𝑦 = 2𝑎𝑥 − 𝑧𝑥 d. 𝑦 = 2𝑎𝑥 + 𝑧𝑥

29. Which ordered pair is a solution of 3x – 2y = 5?

a. (1, -1) b. (2, 1) c. (-1, 1) d. (-2, 1)

30. Which answer shows the domain and range of the curve that is graphed?

a. 0 ≤ 𝑥 ≤ 4 and 0 ≤ 𝑦 ≤ 36

b. 0 ≤ 𝑥 ≤ 36 and 0.5 ≤ 𝑦 ≤ 3.5

c. 0.5 ≤ 𝑥 ≤ 3.5 and 0 ≤ 𝑦 ≤ 36

d. 1 ≤ 𝑥 ≤ 3.5and 0 ≤ 𝑦 ≤ 36

31. A tapeworm lives inside the intestines of a cow and feeds by absorbing food that the cow has

already digested. This is an example of ________.

a. competition b. commensalism c. mutualism d. parasitism

32. As soon as bleeding occurs, platelets ________.

a. begin to clump together in the damaged area.

b. release a variety of chemicals that react with proteins in the plasma.

c. form a plug that helps reduce blood loss.

d. All of the above

33. In the lungs, each bronchiole branches to form thousands of tiny sacs called ________.

a. tracheas b. capillaries c. bronchiolini d. alveoli

34. When cells use protein for energy, a by-product is a harmful substance called ____, which contains nitrogen.

a. ureter b. urethra c. Urea d. Nephrons



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35. As rocks move farther away from mid-ocean ridges, they lose thermal energy and become more dense,

causing ________.

a. subduction b. sea-floor spreading c. uplift d. subsidence

36. In the diagram, which type of tectonic plate motion is

occurring at A?

a. ridge push

b. slab pull

c. convection

d. sea-floor spreading

37. Which of the following statements about subsidence in rift zones is true?

a. The blocks of crust in the center of the rift zone drop down relative to the blocks at the edge of the

rift zone.

b. The lithosphere becomes stretched in rift zones, which causes a large amount of stress to build up.

c. A series of faults forms along a rift zone.

d. all of the above

38. Which of the following are the hottest stars?

a. orange stars b. red stars c. yellow stars d. blue stars

39. ____ is a measure of how far east an object is from the point at which the sun appears on the first day of

spring.

a. Horizon b. Right ascension c. Declination d. Altitude

40. Which of the following does NOT depend on where you are and when you look at a star?

a. celestial sphere b. horizon c. altitude d. constellation positions

41. Translate into an inequality: The sum of two consecutive odd integers is at most 35.

a. n + (n + 1) >35 b. n + (n + 1) < 35 c. n + (n + 2)≥ 35 d. n + (n + 2)≤ 35

42. Which situation best describes the scatterplot?

a. There are 15 members in the math club

and each one contributes $5.

b. The current value of a baseball card is

$15 and it increases by 5% per year.

c. A store charges $15 to rent a DVD

player plus $5 for each movie rented.

d. Jane is 15 miles from home and jogs

back at a rate of 5 miles per hour.



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43. What is the slope of the line that passes through (2, 15) and (0, -1)?

a.1

8 b.

1

7 c. 7 d. 8

44. Which equation best represents the relation in the table?

a. y = 4x – 5

b. y = x + 10

c. y = 3x

d. y = 1

3x

45. Find the solution of the equation |2x – 3| = 5.

a. x = -4 or x = 4 b. x = -4 or x = 3 c. x = -1 or x = 4 d. x = -1 or x = 3

46. What would BAC be classified as?

a. acute

b. obtuse

c. right

d. scalene

47. Point C is between points A and B. Point D is the midpoint of AC . AB = 20 and DC = 6. Find CB .

a. 6 b. 10 c. 8 d. 14

48. If XY = 10 and XY + BC = 18, then 10 + BC = 18 is an example of what property?

a. transitive property

b. addition property

c. substitution property

d. symmetric property

49. All the interior angles in an octagon add to what?

a. 360° b. 1080° c. 1500° d. 180°

50. What is the measurement of x?

a. 6°

b. 180°

c. 96°

d. 98°



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51. Examine the table below.

Types of Stars

Class Color Surface temperature ( C) Elements detected

O blue above 30,000 helium

B blue-white 10,000–30,000 helium and hydrogen

A blue-white 7,500–10,000 hydrogen

F yellow-white 6,000–7,500 hydrogen and heavier elements

G yellow 5,000–6,000 calcium and other metals

K orange 3,500–5,000 calcium and molecules

M red less than 3,500 molecules

An example of a class O star is 10 Lacertae. What is its chemical composition?

a. helium

b. helium and hydrogen

c. hydrogen

d. calcium and other metals

52. The actual brightness of a star is called its ________.

a. relative brightness

b. apparent magnitude

c. absolute magnitude

d. parallax

53. Which statement about sound is true?

a. Air particles travel with sound waves.

b. Sound waves can travel in a vacuum.

c. Sound waves are transverse waves.

d. Air particles vibrate along the path of a sound wave.

54. Thunder consists of ________.

a. only low-frequency sound waves.

b. only high-frequency sound waves.

c. both high- and low-frequency sound waves.

d. neither high- nor low-frequency sound waves.

Use the information below to answer questions 55 and 56.

The following statements contain information regarding the roach population.

A. Roaches that live to maturity may mate and produce offspring.

B. A population of roaches contain some pesticide-resistant roaches and some that are not resistant to

pesticides.

C. Many roaches do not survive because they come in contact with pesticides.

D. Roaches lay many eggs.



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55. Which of the above statements most closely illustrates genetic variation?

a. A b. B c. C d. D

56. Which of the above statements most closely illustrates struggle to survive?

a. A b. B c. C d. D

57. The soupy mixture of food, enzymes, and acids in the stomach is called

a. chyme b. villi c. urea d. vitamins

58. A __________ is a wave in which the particles of the medium are displaced in a direction parallel to the

direction of energy transport.

a. Transverse Wave b. Surface Wave c. Lateral Wave d. Longitudinal Wave

59. Nonmetal atoms gain electrons and become __________, negatively charged ions.

a. Anions b. Cations c. Isotopes d. Valences

60. The probability of a child carrying a BB genotype between a homozygous (BB) parent and a heterozygous

parent (Bb) is __________.

a. 1/2 b. 1/4 c. 3/4 d. 0/4

61. A flower casts a shadow 6 ft. long. At the same time, a 20 ft. tall tree casts a shadow which is 80 feet long.

How tall is the flower?

a. 2 ft. b. 1.5 ft. c. 260 ft. d. 1 ft.

62. Simplify:

1

12

3

1

x

x

a. (x + 1)2 = 6 b. x + 1 = 36 c. x + 1 = 6 d. (x + 1)2 = 36

63. A traveling salesman visited three towns in one day. He started at Agroville then walked 5 miles west to get

to Betterville then traveled 10 miles north to get to Countryland. How far is it from Agroville to

Countryland?

a. 10 b. 11.18 c. 12.23 d. 15

64. What is the equation for a circle with a radius of 4 and a center at (1,1)

a. (x – 1)2 + (y – 1)2 = 4

b. (x – 1)2 + (y – 1)2 = 16

c. (x – 1) + (y – 1) = 16

d. (x + 1)2 + (y + 1)2 = 16



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65. What is the volume of a cylinder with a radius of 2 in. and a height of 10 in?

a. 125.7 in.3 b. 62.8 in.3 c. 12.6 in.3 d. 100 in.3

66. A man is climbing to the top of the Empire State Building. After 10 minutes, he is at 100 feet and after 20

minutes he is at 200 feet. What equation represents the relationship between h, the man’s elevation at a

certain time, t.

a. h = 10t b. h = -10t c. h = 10t + 10 d. h = -10t + 10

67. Solve: 2x + 4y = -10

2x – y = 20

a. x = 10 , y = 7 b. x = 7 , y = -6 c. x = 7 , y = 6 d. x = 10 , y = -7

68. Find the point of intersection between the following two lines: y = 3x - 4

y = 2x + 8

a. (32, 12) b. (12, 32) c. (-32,-12) d. (-12,-32)

69. Solve for x: x2 – 7x + 5

a. 2

297 b.

2

235 c.

5

314 d. -1 , 1

70. Simplify:

5

105 x

a. x + 2 b. x – 2 c. 5 d. x + 5

71. When you conduct a controlled experiment, which one of these describes the condition that is changed?

a. The independent variable

b. The dependent variable

c. The data

d. The observation

72. The statement “the snake is 5 cm long” is a(n)

a. Inference

b. Hypothesis

c. Quantitative observation

d. Qualitative observation



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73. Which would an animal breeder use to produce cows that give more milk?

a. Genetic isolation

b. Artificial selection

c. Acquired characteristics


74. The large ground finch obtains food by cracking seeds. Its short, strong beak is an example of

a. An adaption

b. A vestigial organ

c. The tendency towards perfection

d. The struggle for existence

75. The type of selection in which individuals at one end of a curve have the highest fitness is called

a. Stabilizing selection

b. Disruptive selection

c. Directional selection

d. The founder effect

76. Weight is ________.

a. a measure of the density of an object

b. always equal to the mass of the object

c. a measure of the pull of gravity

d. the amount of matter in an object

77. A measure of how close the atoms are packed is called ________.

a. temperature b. plasma c. atomic number d. density

78. Which of the following is not a property of a compound?

a. physical combination of substances

b. parts make new properties

c. parts must be present in exact amounts

d. hard to separate

79. Which of the following has the greatest penetrating ability?

a. X-rays b. gamma rays c. radio waves d. ultraviolet rays

80. Newton's first law of motion describes ________.

a. how balanced forces affect motion

b. how unbalanced forces affect motion

c. why forces are always in pairs

d. all parts and types of motion



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Answer key

1 A 41 D

2 B 42 C

3 C 43 D

4 D 44 C

5 B 45 C

6 A 46 A

7 C 47 C

8 C 48 C

9 D 49 B

10 C 50 C

11 C 51 A

12 D 52 C

13 D 53 D

14 C 54 C

15 C 55 B

16 C 56 C

17 D 57 A

18 D 58 D

19 C 59 A

20 B 60 A

21 B 61 B

22 A 62 D

23 A 63 B

24 B 64 B

25 A 65 A

26 A 66 A

27 B 67 B

28 B 68 B

29 A 69 A

30 C 70 A

31 D 71 A

32 D 72 C

33 D 73 B

34 C 74 A

35 D 75 C

36 B 76 C

37 D 77 D

38 D 78 A

39 B 79 B

40 A 80 A


8th grade practice test - divisional stem competition · 8th grade practice test - divisional stem...

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