Aman is redecorating his bedroom .he can choose from 5 paint colors 6 beds and 5 dressers how many ways can he choose to design his room

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?