Five coins were simultaneously tossed 1000 times and at each toss the numbers 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 | 38 |
1 | 144 |
2 | 342 |
3 | 287 |
4 | 164 |
5 | 25 |
Total | 1000 |
No. of heads per toss (x) | No. of tosses (y) | yx |
0 | 38 | 0 |
1 | 144 | 144 |
2 | 342 | 684 |
3 | 287 | 861 |
4 | 164 | 656 |
5 | 25 | 125 |
Mean number of heads per toss = 
= 
= 2.47
Therefore, mean = 2.47
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