Siebel , whose fortunes soared with the tech boom , has cut nearly one-third of its workforce since the end of 2001 .
With the purge , Siebel will have cut 2,400 employees - or nearly one-third of its workforce - since the end of 2001 .
for a random variable, describes how probabilities are distributed over the values of the random variable  - can use with a table, graph, or formula