For each of these three prompts, you should attempt to ‘play around’ with the question to define the pattern(s) involved – using the same approach showcased in the prior post. An explanation for how to approach each prompt in such a way will be provided tomorrow.
 
1) How many positive integers, from 2 to 100, inclusive, are not divisible by odd integers greater than 1?
 
A. 5
B. 6
C. 8
D. 10
E. 50
 
 
2) There are 20 doors marked with numbers 1 to 20 and there are 20 individuals marked 1 to 20.
 
An operation on a door is defined as changing the status of the door from open to closed or vice versa. All doors are closed to start with.
 
One at a time, one randomly picked individual goes and operates the doors. The individual operates only those doors which are a multiple of the number he/she is carrying. For example, the individual marked with the number 5 only operates the doors marked with the following numbers: 5, 10, 15 and 20.
 
If every individual in the group gets one turn, then how many doors are open at the end?
 
A. 0
B. 1
C. 2
D. 4
E. 6
 
 
3) A test has 200 questions. Each question has 5 options, but only 1 option is correct. If test-takers mark the correct option, then they are awarded 1 point. However, if an answer is incorrectly marked, the test-taker loses 0.25 points. No points are awarded or deducted if a question is not attempted. A certain group of test-takers attempted different numbers of questions, but each test-taker still received the same net score of 40.  What is the maximum possible number of such test-takers?
 
A. 31
B. 33
C. 35
D. 40
E. 42
 
 
GMAT assassins aren’t born, they’re made,
Rich
 
If you have any questions about anything in this thread, then you can feel free to contact me directly via email (at [email protected])