A locker combination has four nonzero digits. If no digit can be repeated and the first three digits are 1-2-3, what is the probability that the fourth digit is 4?
A. 1/6
B. 1/7
C. 1/8
D. 1/9
Since the combination has already used 1, 2, and 3. Then the 4th digit must be either 4, 5, 6, 7, 8, or 9.
So the probability must 1 out of 6 or 1/6.
thank you, ms. sue! that's what i thought it was but i was confused. :)
With your data, I am confused too. How many total numbers are there?
Since the first 3 numbers cannot be repeated, the answer = 1/(total-3)