The digits 3, 4, 5, 6 and 7 are randomly arranged to form a three-digit number. Digits are not repeated. What is the probability that the number is even and greater than 700?
1 Answer
Dec 14, 2017
Explanation:
There are
To satisfy the conditions, we want the first digit to be 7. We want the last digit to either be 4 or 6. With the 7 forced to be the first digit, we have 4 digits to account for.
To get an even digit, we have a population of 2 and we are choosing 1:
We can now account for the remaining 3 digits, which is
Therefore, the number of ways to get an even number greater than 700 is:
and the probability of randomly arranging numbers into this arrangement is: