3*10*10*9
check that. The last nine allows no 000
How many different sequences of 4 digits are possible if the first digit must be 3, 4, or 5 and if the
sequence may not end in 000? Repetition of digits is allowed
2 answers
Or would it be:
3 for the first number (either a 3,4 or 5)
10 for the second number (a 0 to 9)
10 for the third number (a 0 to 9)
10 for the fourth number (a 0 to 9)
take off numbers that end in 000 so 3000, 4000, 5000 (so take off 3)
=
3 x 10 x 10 x 10 -3
3000-3 = 2997
3 for the first number (either a 3,4 or 5)
10 for the second number (a 0 to 9)
10 for the third number (a 0 to 9)
10 for the fourth number (a 0 to 9)
take off numbers that end in 000 so 3000, 4000, 5000 (so take off 3)
=
3 x 10 x 10 x 10 -3
3000-3 = 2997
0 answers