Inferences A
#42 What is the IQR?
40. . . IQR is Q3 - Q1 or size of the box.
#51 Sam surveys the entire student body . . . which describes the distribution for each graph? see graphs and options in study guide
B. radio = skewed right and MP3 = symmetric . . . remember skewed right is not a lot on the right. symmetric is kinda mountain shaped
#34 Brenna is doing an experiment with a number cube. She rolled the cube 24 times. How many times should she expect the cube to land on a 6?
4 times . . . P(6) = 1/6. . . 1/6 of 24 = 4
#38 A triangular bike path is exactly 9 miles long. If each of the three connecting paths is a whole-number of miles long, which could be the lengths of the paths? See options in study guide
D. 2 miles, 3 miles, 4 miles . . . the two short sides have to sum to be bigger than the longest side
#5 in study guide
B. octagon
D all of the above
#50 Two sets of data are graphed on the line plot. What observation can you make about the two data sets? see graph and options in study guide
A. both have the same spread . . . aka range
#36 Tree diagram for flipping a penny, nickel, and dime.
C
#39 Find the measurement of angle ACD
150 degrees . . . find the measure of angle ACB first by knowing the sum of the angles in a triangle is 180. angle ACB = 30. Then think how ACB and ACD are related (supplementary = 180) to finish solving
#47 How would you slice a right rectangular prism to create a pentagon?
slice through 5 of the 6 faces
#41 Sylvia has a plastic container of 45 wooden shapes. . . read the rest in your study guide and the answer choices
D. because the larger shapes are more likely to be picked because of their size.
#53 Mr. Adams asked two random groups of 20 students . . . read rest and see options in study guide
B. data for Group B is more spread out than data for Group A . . . IQR is one measure of spread
#35 Rico spins the spinner twice and calculates the product of the spins. What is the probability that Rico will get a product of 20?
2/9 . . . list out all possible spin combinations (2,2), (2,4), (2,5), (4,2), (4,4), (4,5), (5,2), (5,4), (5,5) and their products. Only two of them have a product of 20 out of 9 combinations.
#37 The lengths of two sides of a triangle measure 9 feet and 21 feet. What is the smallest whole number value that the third side could measure? See options in study guide
C. 13 feet . . . needing the smallest for the 3rd side means that 21 is the largest side. So we need to figure out 9 + ___ > 21.
What day is your exam?
5th - Tuesday
1st and 6th - Wednesday
7th - Thursday
#43 In which survey was a parameter reported? see options in study guide
A. “Of the 30 students in Jill’s music class, 1 out of 5 of them know the music of composer Claude Debussy.” . . . the 30 students in Jill's music class are all the students in her class. For the other options, the group surveyed is not everyone in the larger group.
#54 A sample of 7th and 8th grade students were asked how many minutes . . . see graph and answer choices in study guide
A. 8th grade students have more variation in the amount of time spent online last night . . . variation would be IQR or range. Sample size cannot be determined with a box plot
#1 in study guide
1/12
#44 How much cardboard would you need to make a shipping carton with dimensions 12 inches x 10 inches x 7 inches?
548 in2
top/bottom = 2 * 12 * 10= 240; front/back = 2 * 10 * 7= 140; sides = 2 * 12 * 7 = 168
#48 Find the surface area of the pyramid
20250 yd2 .. . area of square base = 75 * 75; area of 4 side triangles = 4 * 0.5 * 75 * 97.5; add those two answers together to get final surface area. the 90 has nothing to do with anything
#46 Jamika wanted to determine whether 7th grade boys or girls can swim faster. She decided to do an experiment where she randomly selected 9 boys and 9 girls to swim one lap. She recorded the time, in seconds, of each swimmer and then plotted the results of her survey. How do the means compare between the girls and the boys?
A. the means are the same
#52 Ali asked a random sample of 10 seventh grade boys and 10 seventh grade girls how to spell . . . see rest and graph and options in study guide
A. The IQR for boys is 1 word greater than the IQR for girls. . . IQR = Q3 - Q1. for boys this is 6 - 3 = 3 for girls this is 6 - 4 = 2
See chart from #14 but now what is P(heart, cat, star)? simplify your answer
1/30 . . . P(heart) = 2/9; P(cat) = 2/5; P(star) = 3/8. multiply them together to get 12/360 then simplify
#45 Find the volume of the barbecue.
104.25 ft3
Volume of larger prism (if there wasn't a hole in it) = 6*4*5 = 120. Volume of the missing chunk = 1.5*3 *3.5 = 15.75. Subtract 120 - 15.75
#55. Mrs. Jones recorded the time she spends reading each day for 2 weeks. Results shown. What is IQR for each week? see data in study guide. You must get both weeks correct to get this question correct
Week 1 = 31 (Q3-Q1 = 81-50)
Week 2 = 25 (79 - 54)