Suppose that the body weights of lemmings are normallydistributed with a mean of 63.8g and a standard seviation of12.2g.
(a) What proportions of lemmings weigh more than 90g ?
(b)What proportion of lemmings weigh between 40 and 90 g?
(c)We can say that 99% of lemmings weigh more than ____ g.
(d)In a random sample of 20 lemmings what is the probabilitythat exactly 3 weigh more than 90g ?
