Five coins were simultaneously tossed 1000 times, and at each toss the number of heads was 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 pre toss(x): 0 1 2 3 4 5 No. of tosses (f): 38 144 342 287 164 25

Question

Philoid · Accepted Answer

Let the assumed mean (A) = 2

No. of heads per toss (x_i)	No. of intervals (f_i)	U_i = x_i - A = x_i - 2	f_iu_i
0	38	-2	-76
1	144	-1	-144
2	342	0	0
3	287	1	287
4	164	2	328
5	25	3	75
	N = 1000		∑f_iu_i = 470

Mean number of heads per toss = A +

= 2 + = 2 + 0.47

= 2.47

No. of heads pre toss(x):	0	1	2	3	4	5
No. of tosses (f):	38	144	342	287	164	25