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Home » An aircraft has 120 passenger seats. The number of seats occupied during 100 flights is given in the following table : Number of seats 100-104 104-108 108-112 112-116 116-120 Frequency 15 20 32 18 15 Determine the mean number of seats occupied over the flights.
An aircraft has 120 passenger seats. The number of seats occupied during 100 flights is given in the following table : Number of seats 100-104 104-108 108-112 112-116 116-120 Frequency 15 20 32 18 15 Determine the mean number of seats occupied over the flights.
Exercise 13.3 | NCERT Exemplar | Statistics and Probability
An aircraft has 120 passenger seats. The number of seats occupied during 100 flights is given in the following table : Number of seats 100-104 104-108 108-112 112-116 116-120 Frequency 15 20 32 18 15 Determine the mean number of seats occupied over the flights.

 

Class Interval      Class Marks (xi)  Frequency (fi)     Deviation (di = xi – a)      fidi

100 – 104            102        15           –8           –120

104 – 108            106        20           –4           –80

108 – 112            110        32           0             0

112 – 116            114        18           4             72

116 – 120            118        15           8             120

N = Σfi = 100                      σfidi = – 8

∴ Assumed mean, a = 110

Class width, h = 4

Also, absolute perceptions, N = 100

Henceforth, discovering mean,

NCERT Exemplar Class 10 Maths Chapter 13 Ex. 13.3 Question 6

    \[=\text{ }110\text{ }+\text{ }\left( -\text{ }8/100 \right)\]

    \[=\text{ }110\text{ }\text{ }0.08\]

= 109.92

However, we realize that the seats can’t be in decimal.

In this way, the quantity of seats = 109.

i

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