An old man while dialing a 7 digit telephone humber remembcrs that the first four digits consists of one I's, one 2's and two 3's. He also remembers that the fifth digit is cither a 4 or 5 while has no memorising of the sixth digit, he remembers that the seventh digit is 9 minus the sixth digit. Maximum number of distinet trials he has to try to make sure that he dials the correct telephone number, is

An old man while dialing a 7-digit telephone number remembers that the first four digits consist of one 1's, one 2's and two 3's. he also remembers that the fifth digit is either a 4 or 5 while has no memory of the sixt digit, he remembers that the seventh digit is 9 minus the sixth digit, maximum number of distinct trials he has to try to make sure that he dials the correct telephone number, is A. 360 B. 240 C. 216 D. none of these

The number of 5 digit telephone numbers having atleast one of their digits repeated is

The number of four digits telephone numbers having atleast one of their digit is repeated

The number of 5- digit telephone number having at least one of their digits repeated is :

The number of five digit telephone numbers having at least one of their digits repeated is

Make the greatest and the smallest: 4-digit numbers with the digit 4,1,0 using any one digit twice.