Question

(a) How many different positive three-digit whole numbers can be formed from the four digits 2, 6, 7, and 9 if any digit can be repeated?

(b) How many different positive whole numbers less than 1000 can be formed from 2, 6, 7, 9 if any digit can be repeated? 

(c) How many numbers in part (b) are less than 680 (i.e. up to 679)? 

(d) What is the probability that a positive whole number less than 1000, chosen at random from 2, 6, 7, 9 and allowing any digit to be repeated, will be less than 680?​

Answer 1

Answer:

5 to 6 4 digit no. formed ok