Piano Sight Reading Advice

We talk about the media, fashion and median

consider the most common measures used to interpret data of a statistical survey

the arithmetic average of 23 students a class were asked to indicate the time taken to reach the school. responses are shown in the table below
Pupil Time (min) A 20


B 12 C 3 D 7


E 5 F 6 G 15

H 5
The 10 L 4


M 7 N 5 O 6

9
P Q R
5 6 7

S T U
10 7 V 10


Z 5 X 18 Y 2

tot. 184
184:23 Average = 8
The value obtained is the arithmetic mean of the times and is the sum of all time divided by the number of pupils.

General:
The arithmetic mean of a set of data is obtained by adding all the data and dividing the result by the number of data

Fashion
In data set is named as the fashion shows with greater frequency, that is because the largest number of times.

We order the data already considered in the following table:
Time (min) Frequency

2 1 3 1 4 1

5 (fashion) 5

6 3 7 4 9 1

10 3 12 1


15 1 18 1 20 1

Fashion is the value 5, which is what is the largest number of times.

Median

We now ascending the 23 values \u200b\u200bthat indicate travel times:

2-3-4-5-5-5-5-5-6-6-6 - 7 - 7 -7-7-9-10-10-10-12-15-18-20

the value that occupies the central place, which is the twelfth place is 7. This value represents the median.

where the values \u200b\u200bare equal in number, take the two core values \u200b\u200band calculate the arithmetic mean.

Ultimately we found three significant values:

8 arithmetic mean: it tells us how long each student would take if everyone takes the same time;

5 fashion: it tells us what is the time used by the largest number of pupils;

median 7 : it tells us that about half the students take less than 7 minutes and takes about half more than 7 minutes.