Three teachers share 2 packs of paper equally.
a: 3 halves of pack
b: 2third of pack
c: 3 sixth of a pack
d: 1 half of a pack
e: 1 third of a pack or

Aparticular telephone number is used to receive both voice calls and fax messages. suppose that 25% of the incoming calls involve fax messages, and consider a sample of 25 incoming calls. (a) what is the expected number of calls among the 25 that involve a fax message?