Question

For this item, any answers that are not whole numbers should be entered as a decimal, rounded to the tenths place. Brian's school locker has a three-digit combination lock that can be set using the numbers 5 to 9 (including 5 and 9), without repeating a number. The probability that the locker code begins with a prime number is %. The probability that the last digit of the locker code is an odd number is %.

Answer 1

Answer:

1. The probability that the locker code begins with a prime number is 40%.
2. The probability that the last digit of the locker code is an odd number is 40%

Step-by-step explanation:

1. Prime numbers are the numbers that only divide with 1 or itself. So in this case it is 5 and 7.

The possible combinations are

1*4*3 (with 5) +  1*4*3(with 7) = 24

Total combinations are 5*4*3=60

(24/60)*100 = 40 %

     2. Odd numbers are those which don't divide with 2. So in this case it is 6 and 8.

The possible combinations are

1*4*3 (with 6) +  1*4*3(with 8) = 24

Total combinations are 5*4*3=60

(24/60)*100 = 40 %