MEDIAN
MODE AND MEAN EXAMPLES:
Example
:
1.Seven
people were asked to guess the number of beans in a jar. Their guesses were 194
, 173 , 170 , 144 , 182 , 259 , 159.
(i)
Find the median.
(ii)
Work out the mean.
Working
:
(i)
Median = 173
A. First you have to arrange the numbers from smallest
to the largest.
144 , 159 , 170 , 173 , 182 , 194 , 259.
B. And then you cancel
the numbers one by one from each side.
(ii)
Mean = 183
A. First you have
to add all the numbers given.
144 + 159 + 170 + 173 +
182 + 194 + 259 = 1281
B. And then divide
the answers that you got with the total numbers.
1281
= 183
7
Example
:
2.Naomi
records the sizes of the 34 pairs of shoes that her shop sells in one day.
4 10
5 6 4
8 6 4
7 3 9
7 4
7 3
5 4 6
5 10 7
5 5 6
4 7
7 6
6 5 5
3 5 6
(i)
Using the list above complete the frequency table :
|
Shoe
size
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
|
frequency
|
|
|
|
|
|
|
|
|
(ii)
Calculate the mean of these shoe sizes.
(iii)
Calculate the percentage of all the pairs of shoes
that are size seven(7).
Working
:
(i)
Using the list above complete the frequency table :
|
Shoe
size
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
|
frequency
|
3
|
6
|
8
|
7
|
6
|
1
|
1
|
2
|
A. First you have
to arrange the numbers and then you count each numbers to find the frequency.
4 10
5 6 4
8 6 4
7 3 9
7 4 3 , 3 , 3 , 4 ,
4 , 4 , 4 , 4 , 4 , 5 , 5 , 5 , 5 , 5 , 5 , 5 , 5
7 3
5 4 6
5 10 7
5 5 6
4 7 6 , 6 , 6 , 6 ,
6 , 6 , 6 , 7 , 7 ,7 , 7 , 7 , 7 , 8 , 9 , 10 , 10
7 6
6 5 5
3 5 6
3 =
3 ,
4 = 6 , 5 = 8
, 6 = 7
, 7 = 6 , 8 =
1 , 9 = 1 , 10 = 2
(ii)
Mean = 5.7
B. Add all the
numbers that are already arranged and divide it by the total numbers.
3 + 3 + 3 + 4 + 4 + 4 + 4 + 4 + 4 + 5 + 5 + 5 + 5 +
5 + 5 + 5 + 5 + 6 + 6 + 6 + 6 + 6 + 6 + 6 + 7 + 7 +7 + 7 + 7 + 7 + 8 + 9 +
10 + 10
34
(iii)
Percentage = 17.6 %
C. Multiple the
numbers of shoes size 7 by the total shoes pairs and divide by hundreds.
6 x 34 = 17.6 %
100
Ulasan ini telah dialihkan keluar oleh pengarang.
BalasPadamif it is a large set of data, and you have to find the mean. is there an easier way or shortcut to calculate and find the answer?
BalasPadam