what is the probability that the last digit is an even number?
what is the probability that the last digit is an even number?
List out the numbers that the card could possibly end in: 0,1,2,3,4,5,6,7,8, or 9.
There are ten digits it could possibly end in. Of those, five are even numbers
SO: the probability that it ends in an even number is (# of even digits)/(total # of digits)
5/10 ---> 1/2
Total Numbers = 10
Even = 0,2,4,6,8 Odd = 1,3,5,7,9
5 Evens and 5 Odds
Number of possible outcomes = 10 (Last digit being even and last digit being odd)
Number of favorable outcomes = 5 (Even)
Probability = Number of favorable outcome/Number of possible outcome = 5/10 = 1/2 = 0.5
(Note that 0 is considered to be even
http://en.wikipedia.org/wiki/Parity_of_zero)
Comments
There are two types of digits, even or odd. The question does not ask for any combination of digits of the store credit. It only asks about the last digit. There are only two possibilities. Either Odd or Even. Hence, there is a 50% chance. Probability = 1/2