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thanx a lot, much appreciated.

**supastar**- Replies: 2

a large number of observations follow a normal distribution with a mean of 120 and a standard deviation of 80. What proportion of observations is:

i) below 100

ii) above 130

iii) between 100 and 130

iv) between 130 and 140

v) between 115 and 135??

anyone have an ideas because I certainly dont

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