Find the probability that a four digit number comprising the digits 2,...
Solution:
To find the probability that a four-digit number comprising the digits 2, 5, 6, and 7 would be divisible by 4, we need to follow the steps given below:
Step 1: Find the total number of ways to form a four-digit number using the digits 2, 5, 6, and 7.
We can use the permutation formula to find the total number of ways to form a four-digit number using four distinct digits. Therefore, the total number of ways to form a four-digit number using the digits 2, 5, 6, and 7 is given by:
4P4 = 4! / (4-4)! = 24
Therefore, there are 24 possible four-digit numbers that can be formed using the digits 2, 5, 6, and 7.
Step 2: Find the number of four-digit numbers that are divisible by 4.
A number is divisible by 4 if and only if its last two digits are divisible by 4. Therefore, we need to consider only the last two digits of each four-digit number to determine if it is divisible by 4. We can use the following cases to find the number of four-digit numbers that are divisible by 4:
Case 1: The last two digits are 2 and 6.
In this case, the first two digits can be any of the remaining two digits. Therefore, the number of four-digit numbers that are divisible by 4 with the last two digits as 2 and 6 is:
2 x 1 x 1 = 2
Case 2: The last two digits are 6 and 2.
In this case, the first two digits can be any of the remaining two digits. Therefore, the number of four-digit numbers that are divisible by 4 with the last two digits as 6 and 2 is:
2 x 1 x 1 = 2
Case 3: The last two digits are 2 and 5.
In this case, the first two digits can be any of the remaining two digits. Therefore, the number of four-digit numbers that are divisible by 4 with the last two digits as 2 and 5 is:
2 x 1 x 1 = 2
Case 4: The last two digits are 6 and 5.
In this case, the first two digits can be any of the remaining two digits. Therefore, the number of four-digit numbers that are divisible by 4 with the last two digits as 6 and 5 is:
2 x 1 x 1 = 2
Therefore, the total number of four-digit numbers that are divisible by 4 is:
2 + 2 + 2 + 2 = 8
Step 3: Find the probability that a four-digit number comprising the digits 2, 5, 6, and 7 would be divisible by 4.
The probability of an event is the number of favorable outcomes divided by the total number of possible outcomes. Therefore, the probability that a four-digit number comprising the digits 2, 5, 6, and 7 would be divisible by 4 is:
8 / 24 = 1 / 3
Therefore, the probability that a four-digit number comprising the digits 2, 5, 6, and 7 would be divisible by