Mean with Frequency

It is assumed that the frequency of each interval is centred around its

• mid point

• lower limit

• upper limit

• none of the above

Find the mean age. You may want to write out the table with an extra column.

• 2.6

• 6.5

• 5.7

• 5.5

Find the mean number of phones. You may want to copy out the table with an extra column.

• 2.56

• 2.3

• 1.5

• 2.2

Find the mean number of pets. You may need to copy out the table with an extra column.

• 0.87

• 1.55

• 1.68

• 1.45

Find the mean, for the given distribution:

• 4.2

• 2.1

• 4

• 2

Answer explanation

The mean of following distribution is

Xi : 11 14 17 20

fi : 3 6 8 7

• 15.6

• 17

• 14.8

• 16.4

Find the mean amount of money. You may want to copy out the table with an extra column.

• £12

• £24

• £30

• £35

• 5

• 7

• 23

• 16

Find the midpoints.

• 25.5, 35.5, 45.5, 55.5, 65.5, 75.5

• 20.5, 30.5, 40.5, 50.5, 60.5, 70.5, 80.5

• 21, 31, 41, 51, 61, 71

• 30, 40, 50, 60, 70, 80

What columns do we need to add to the table to calculate the mean temperature? (Tick all that apply)

• Total of the 'number of days with that temperature' column

• Total of the 'temperature column'

• 'fx' column for the product of the first two columns

• Total of the 'fx' column