math30
posted by alejandro .
The number of three digit or four digit even numbers that can be formed from the numbers 2, 3, 5, 7 is
A.72
B.120
C.144
D.5040

Question:
Can digits be repeated,
e.g. is 332 allowed as a 3 digit number?
both groups must end with a "2"
I will assume digits may repeat
number of 3 digit even numbers = 4x4x1 = 16
number of 4 digit even numbers = 4x4x4x1 = 64
total = 80
mmhhh?
suppose we can't repeat
3digit evens = 3x2x1
= 6
4digit evens = 3x2x1x1 = 6
that would be only 12 total
something is not right with your choices.
Am I reading the question correctly? 
Reiny I just realized "even meter" means not repeated.
That help???? 
Reiny I just realized "even numbers" means not repeated.
That help????