Q11 of 79 Page 24

Five coins were simultaneously tossed 1000 times and at each toss the number of heads were observed. The number of tosses during which 0, 1, 2, 3, 4 and 5 heads were obtained are shown in the table below. Find the mean number of heads per toss.















No. of heads per toss



No. of tosses



0


1


2


3


4


5



38


144


342


287


164


25



Total



1000












































No. of heads per toss (x)



No. of tosses (f)



fx



0



38



0



1



144



144



2



342



684



3



287



861



4



164



656



5



25



125




N = 1000



∑fx = 2470



Therefore, mean number of heads per toss =


=


= 2.47


More from this chapter

All 79 →
9

Find the mean of the following distribution.



















x:



10



12



20



25



35



f :



3



10



15



7



5


 10

Candidates of four schools appear in a mathematics test. The data were as follows:













Schools



No. of Candidates



Average Score



I


II


III


IV



60


48


Not available


40



75


80


55


50



If the average score of the candidates of all the four school is 66, find the number of candidates that appeared from school III.

 12

Find the missing frequencies in the following frequency distribution if it is known that the mean of the distribution is 50.





















x:



10



30



50



70



90




f :



17



f1



32



f2



19



Total 120.


 1

Find the median of the following data

83, 37, 70, 29, 45, 63, 41, 70, 34, 54