The ages, in years, of 5 boys are 5, 6, 6, 8 and 10. Calc...
The ages, in years, of 5 boys are 5, 6, 6, 8 and 10. Calculate, correct to one decimal place, the standard deviation of their ages.
3.2 years
2.6 years
1.9 years
1.8 years
Correct answer is D
| x | 5 | 6 | 6 | 8 | 10 | Total |
| x−ˉx | -2 | -1 | -1 | 1 | 3 | |
| (x−ˉx)2 | 4 | 1 | 1 | 1 | 9 | 16 |
Mean (ˉx) = 5+6+6+8+105
= 355=7
SD=√∑(x−ˉx)2n
= √165
= √3.2
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