7th grade math

Question 1

the sum of the data values divided by the number of data items

Answer 1

mean

Question 2

the middle value of an odd number of data items arranged in order

Answer 2

median

Question 3

What do you do to find the median of an even number of data items?

Answer 3

the median is the mean of the two middle numbers

Question 4

the value or values that occur most often

Answer 4

mode

Question 5

What is the mode if the data values occur the same number of times?

Answer 5

There is no mode.

Question 6

the difference between the greatest and the least values

Answer 6

range

Question 7

Find the mean of the following numbers:

2,1,8,0,2,4,3,4

Answer 7

mean = 24/8 = 3

Question 8

Find the median of the following numbers:

2,1,8,0,2,4,3,4

Answer 8

0,1,2,2,3,4,4,8 - even
The two middle numbers are 2 and 3
2+3 = 5 5/2 = 2.5

Question 9

Find the mode of the following numbers:

2,1,8,0,2,4,3,4

Answer 9

0,1,2,2,3,4,4,8

The modes are 2 and 4 because they both occur twice.

Question 10

Find the range of the following numbers:

2,1,8,0,2,4,3,4

Answer 10

0,1,2,2,3,4,4,8

largest - smallest 8-0 = 8

Question 11

What are the measures of central tendency?

Answer 11

mean, median, mode

Question 12

What is the meaning of measuring central tendency?

Answer 12

finding the middle

Question 13

When is mean most useful?

Answer 13

when the data are spread evenly

Question 14

When is the median most useful?

Answer 14

when the data set has an outlier

Question 15

When is mode most useful?

Answer 15

when knowing which data point receives the most is important like in an election

Question 16

an extreme value very different from the others

Answer 16

outlier

Question 17

using a number line to show the distribution of a set of data

Answer 17

box-and-whisker plot

Question 18

In a box-and-whisker plot, the median of the lower half is called what?

Answer 18

lower quartile

Question 19

In a box-and-whisker plot, the median of the upper half is called what?

Answer 19

upper quartile

Question 20

the difference between the lower and upper quartiles or the length of the box

Answer 20

interquartile range

Question 21

the smaller the interquartile range tells us what about the data

Answer 21

more predictable

Question 22

what is an entire group called

Answer 22

population

Question 23

what is a part of a population called

Answer 23

sample

Question 24

when samples are chosen where everyone has an equal chance of being chosen

Answer 24

random sample

Question 25

when samples are based upon individuals that are readily available

Answer 25

convenience sample

Question 26

a sample that doesn’t fairly represent the population

Answer 26

biased sample

Question 27

why would you want to use a sample instead of the entire population

Answer 27

if population is large

Question 28

why is it difficult to get a truly random sample

Answer 28

not convenient