Name ______Date ______
’12-’13 REVIEW for 7ACC U6 STATISTICS Test
Part 1 – NO calculator
A middle school has 350 students. One math class wants to find out how many hours a typical student in the school spent doing homework last week. Use this information to answer questions 1 and 2 below.1)Which sampling method will give you data that lets you make accurate predictions about the population?
a)Ask the students in 6 different ELA classes
b)Ask all the students who attend the after-school homework help club
c)Each student places his/her name in a container as they enter the school. 30 names
are selected from the container and those students are asked.
d)A morning announcement is made that we are looking for 40 volunteers to answer a survey question.
2)Now, suppose an appropriate method is chosen to survey students. Out of the 50 students who are asked, 35 students said they spent 10 hours doing homework last week. How many students of the 350 students in the middle school would you expect spent 10 hours a week on HW?
3)In a basketball contest, Chad predicted he would make 85 percent of his shots. He actually made 18 out of 20 shots. How did Chad's prediction compare with his actual results?
a)His prediction was the same as his actual results.
b)His prediction was lower than his actual results.
c)His prediction was higher than his actual results.
d)His prediction cannot be compared with his actual results.
4)A class of 14 students recently took a math test. Their scores are listed below.
46, 58, 67, 68, 70, 72, 77, 77, 79, 82, 85, 90, 90 94
Which of the following values represents the third quartile?
a)68 b) 77 c) 85 d) 94
b)
5)
40 middle schools were asked to determine what the average class size was for their math classes. That is, as anaverage, how many students are placed in each math class? The box plot shows the results for this survey. Use this to answer questions 6 - 12
6)What is the median number of students placed in a math class?
7)How many schools have fewer than 14 students in a class?
8)Which value represents the lower quartile?
Decide if each statement is true, false or cannot be determined:
9)25% of the schools surveyed have, on average, more than 19 students in their math classes.
10)The mean number of students in a math class is 17.
11)50% of the schools have between 14 and 19 student’s in their math classes.
12)30 schools have fewer than 19 students in their math classes.
Part 2 – you MAY use a calculator
13)From ages 5 – 18, the average student eats 1,500 peanut butter and jelly sandwiches. You can make about 15 sandwiches from an 18-ounce jar of peanut butter. How many jars of peanut butter would you need to make 1500 sandwiches?14) Two friends play on two separate basketball teams. They were comparing their average number of points scored per game for the past season. Player A made an average of 36 points with a mean absolute deviation of 8. Player B made an average of 38 points with a mean absolute deviation of 16. Each player argued that she was the better player.
Who do you think is the better player and explain why.
15)The two data sets below depict random samples of the housing prices sold in the King River and Toby Ranch areas of Arizona. Based on the prices below which measure of center will provide the most accurate estimation of housing prices in Arizona? Explain your reasoning.
o King River area {1.2 million, 242000, 265500, 140000, 281000, 265000, 211000}
o Toby Ranch homes {5million, 154000, 250000, 250000, 200000, 160000, 1 90000}
The brake reaction time was tested on 240 motorists. The data is summarized into the quartiles: Q1 = 1.1 seconds Q2 = 1.6 seconds Q3 = 2.5 seconds
Use this information to answer questions 16 – 19.
16) How many motorists have a brake reaction time of less than 2.5 seconds?
17)How many motorists have a brake reaction time of more than 1.1 seconds but less than 1.6 seconds?
18) What is the median brake reaction time?
19)If there are 11.3 million licensed drivers in NYS, and assuming this is a representative sample, about how many drivers in NYS would you expect have a reaction time of
1.1 seconds or less?
The table at the right shows the mean maximum
daily temperatures for each month in Miami
and San Diego.
20)Create a box and whisker plot showing
this data. Be sure to include a table showing
the 5 data points (the info needed for the
box plot). (use the number line given below)
21) Find the mean absolute deviation for
each city. Show your work.
22) Based on your work above, in which city
are the high temperatures for the year
more consistent? Explain how you know.