SOLUTION: student was asked to form two-digit numbers using the following digits: 0,1,2,3,4,5,6,7, and 8 How many of these are less than 40? Repeating of digits are not allowed Can you h

Algebra ->  Permutations -> SOLUTION: student was asked to form two-digit numbers using the following digits: 0,1,2,3,4,5,6,7, and 8 How many of these are less than 40? Repeating of digits are not allowed Can you h      Log On


   

Question 1173434: student was asked to form two-digit numbers using the following digits: 0,1,2,3,4,5,6,7,
and 8
How many of these are less than 40?
Repeating of digits are not allowed
Can you help me with this?.... thank you so much
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

9 numbers:  0,1,2,3,4,5,6,7,8

How many of these are less than 40?

 tens digit: 3 allowed (1,2,3)

 ones digit: 9  allowed

  3x9 = 27 two-digit numbers  less than 40

Repeating not allowed: 11,22,33

 27 - 3 = 24  two-digit numbers less than 40, Repeating not allowed