Math Is Fun Forum

Hello,

I have a couple of questions I need some assistance in.  If anyone can please help me get started with this I appreciate it:

1.  Heights of women have a bell-shaped distribution with a mean of 165cm and a standard deviation of 5cm.  Using Chebyshev's theorem, what do we know about the percentage of women with heights that are within 2 standard deviations of the mean?  What are the minimum and maximum heights that are within 2 standard deviations of the mean?

At least ___% of women have heights within 2 standard deviations of 165cm?  (Round to the nearest percent as needed)
The minimum heights that is within 2 standard deviations of the mean is ___cm
The maximum height that is within 2 standard deviations of the mean is ___cm

2.  Ted is not particularly creative.  He uses the pickup line " If I could rearrange the alphabet.  I'd put U and I together".  The random variable x is the number of girls Ted approaches before encountering one who reacts positively.  Determine whether the table describes a probability distribution.  If it does, find its mean and standard deviation.
x      P(x)
1      0.002
2      0.026
3      0.119
4      0.265
5      0.234

Find the mean of the random variable.  Select the correct choice below and, if necessary.  Fill in the answer box to complete your choice.
a-
b- the table is not a probability distribution

Find the standard deviation of the random variable x.  Select the correct choice below and if necessary fill in the answer box to complete your choice.
a-
b- the table is not a probability distribution

Thank you everyone for your assistance.