Answer:
A 4 digit PIN is selected. What is the probability that there are no repeated digits?
There are 10 possible values for each digit of the PIN (namely: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9), so there are 10 × 10 × 10 × 10 = 104 = 10000 total possible PINs.
To have no repeated digits, all four digits would have to be different, which is selecting without replacement. We could either compute 10 × 9 × 8 × 7, or notice that this is the same as the permutation 10P4 = 5040.
The probability of no repeated digits is the number of 4 digit PINs with no repeated digits divided by the total number of 4 digit PINs. This probability is
6. No, the conclusions wrong because 20 out of 50 peoples favourite is drawing which means 20/50 which equals 0.4 times 100 which is 40% not 60%
7. Yes, the conclusion is right because 5/50 is equal to 0.1 times 100 which is 10%
First step
12 x 1.3
Second step
15.6 x 7.5
The answer is 117 :)