Identifying the Prime Number
To solve this problem, we need to first identify the prime number between 70 and 100. Prime numbers are numbers that are greater than 1 and can only be divided by 1 and themselves without leaving a remainder.

Identifying the Tens and Ones Digits
The condition given in the problem states that the ones digit is two less than the tens digit. This means that the tens digit must be greater than the ones digit by 2.

Applying the Conditions
Let's start by looking for prime numbers between 70 and 100:
- 71, 73, 79, 83, 89, 97
Now, we need to check the tens and ones digits for each of these numbers:
- For 71: Tens digit = 7, Ones digit = 1 (7 - 2 = 5, which is not the ones digit)
- For 73: Tens digit = 7, Ones digit = 3 (7 - 2 = 5, which is the ones digit)
- For 79: Tens digit = 7, Ones digit = 9 (7 - 2 = 5, which is not the ones digit)
- For 83: Tens digit = 8, Ones digit = 3 (8 - 2 = 6, which is not the ones digit)
- For 89: Tens digit = 8, Ones digit = 9 (8 - 2 = 6, which is not the ones digit)
- For 97: Tens digit = 9, Ones digit = 7 (9 - 2 = 7, which is not the ones digit)

Final Answer
The only number that satisfies all the conditions given in the problem is 73. Therefore, the number we are looking for is 73.