[rania9]

In a normal distribution with a mean of 240, 34% of the population lies between 220 and 260.
The standard deviation of the distribution is?

As mean is 240 and 34% lies between 220 & 260 ,the standard deviation will be between 240 & 260 ,that means at the half of 34% ,so 17% .
260-240/s =17% and from the table 0.44 so 260-240/s=0,44=20/0.44=s=45.45

Could you please advise if the answer is correct?
where s=standard deviation

[rania9]

My apologies ,I submitted it to the wrong forum ,it is for BA2.

Thank you

[rania9]

I think ,I found the answer but please advise if my concern is right.

Thank you in advance.

As mean is 240 and 34% lies between 220 & 260 ,the standard deviation will be between 240 & 260 ,that means at the half of 34% ,so 17% .
260-240/? =17% and from the table 0.44 so 260-240/?=0,44=20/0.44=?=45.45

[Author]

Posts