Question

counting question

Answer 1

Using digits {0,1,2,3,4,5,6} how many 4 digit numbers greater than 3000 can be
formed if repetition is allowed ?

Answer 2

I am not sure

Answer 3

the digit in the thousands place can be 3,4,5,6
the digit in the hundreds place can be 0,1,2,3,4,5,6
the digit in the tens place can be 0,1,2,3,4,5,6
the digit in the ones place can be 0,1,2,3,4,5,6

Answer 4

Multiply the number of ways for each, then subtract 1 to exclude 3000

Answer 5

4*7*7*7=

Answer 6

this one ?

Answer 7

yes, then subtract 1 to reject 3000

Answer 8

4*7*7*7-1

Answer 9

I believe that is correct

Answer 10

thanks