Hi All,
As 'thick' as this question might appear, it can be solved with a bit of 'brute force' and a combination of basic arithmetic skills. We can use the answer choices and TEST THE ANSWERS, but we'll also need to 'play around' a bit with the information that we're given (so we can determine what answers are possible and what answers are not).
We're given a number of facts about the variables A, B and C:
1) They're POSITIVE INTEGERS
2) Their average is 20
3) A ≤ B ≤ C
4) The median is (A + 11)
We're asked for the LEAST possible value of C.
To start, since there are 3 variables, we know that B is the median. So we can think of the three variables as A, (A+11) and C. By extension, we know that A is NOT 'close' to C; this means that A is probably a lot less than the average and C is well ABOVE the average.
The average of the variables is 20, so their sum is 60.
Let's TEST 23...
IF....
C = 23
A+A+11 = 37
2A = 26
A = 13
The numbers would be 13, 24 and 23...
This is NOT possible (B ≤ C is not true in this case)
ELIMINATE 23.
Let's TEST 24...
IF....
C = 24
A+A+11 = 36
2A = 25
A = 12.5
This is NOT possible (the variables have to be INTEGERS)
ELIMINATE 24.
Let's TEST 25...
IF....
C = 25
A+A+11 = 35
2A = 24
A = 12
The numbers would be 12, 23 and 25...
This MATCHES everything we were told, so this MUST be the answer.
Final Answer:
GMAT assassins aren't born, they're made,
Rich