S and T are two-digit positive integers that have the same digits but in reverse order. If the positive difference between S and T is less than 50, what is the greatest possible value of S minus T?  Choose the correct answer.
A) 40
B) 42
C) 44
D) 45
E) 48
A two-digit integer "ab" can be expressed algebraically as 10a+b.   S-T=(10a+b)-(10b+a)=9(a-b)&lt;50.   The greatest multiple of 9 which is less than 50 is 45.   The answer is 45.
<result>D</result>
S and T are two-digit positive integers that have the same digits but in reverse order. If the positive difference between S and T is less than 50, what is the greatest possible value of S minus T?