The mean weight of a fire ant worker is 3.11 mg with a
standard deviation of 0.49 mg. Let us assume that the weight of any
fire ant is independent from the weight of any other fire ant. A
typical fire ant colony contains 240,000 fire ant workers. Suppose
we look at the weight of each ant in a typical fire ant colony. Let
M be the random variable representing the mean weight of all the
worker ants in the colony in mg. Let T = the random variable
representing the sum of the weights of all the worker ants in the
colony in mg.
a) What theorem will let us treat T and M as approximately
normal random variables?
Monte Carlo Theorem Central Limit Theorem Chebychev's Theorem
Convolution Theorem Law of Large Numbers
b) What is the expected value of T?
c) What is the standard deviation of T?
d) If TK is T measured in grams (use 1g = 1000mg.), then what
is the standard deviation of TK?
e) What is the approximate probability that T is greater than
747000?
f) What is the standard deviation of M?
g) What is the approximate probability M is between 3.111 and
3.112?
h) What is the approximate probability that T is within 2
standard deviations of its expected value?