one way for first digit, 10 different possiblities for 2nd and 3rd place, 9 ways for unit digit
1x10x10x9 = ?
How many different positive four-digit integers can be formed if the first digit must be 2, the last digit cannot be 0, and digits may be repeated?
a) 336
b) 900
c) 1000
d) 9000
e) 10000
1 answer
2 answers