A shipping company handles containers in three different sizes: (1) 27 ft3 (3  3  3), (2) 125 ft3

, and (3) 512 ft3

. Let Xi (i
1, 2, 3) denote the number of type i containers shipped during a given week. With i
E(Xi

) and 2 i
V(Xi

), suppose that the mean values and standard deviations are as follows:

1
200 2
250 3
100 1
10 2
12 3
8