Posted by Urgen please help on .
Suppose that people's heights (in centimeters) are normally distributed, with a mean of 175 and a standard deviation of 6. We find the heights of 60 people.
(a) How many would you expect to be between 167 and 183 cm tall?
(b) How many would you expect to be taller than 170 cm?

ALGEBRA 
bobpursley,
http://davidmlane.com/hyperstat/z_table.html is an excellent calculator. Enter mean, std deviation, then look at the shaded areas. You can multipy those by 60 to get numbers.