5 - 760+: Test Your Pattern-Finding Skills on These 3 PS Questions
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?
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?
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?
GMAT assassins aren’t born, they’re made,
If you have any questions about anything in this thread, then you can feel free to contact me directly via email (at [email protected])