CAT IS A MCQ BASED EXAMINATION! Ya ya...you all must be knowing this but many a times we forget this at a time of writing a paper. Options are your best friends. Many of the CAT and other MBA entrance exams questions are designed in such a way that you just can't solve them without use of options. If you try to get you answer by solving questions, I am sorry to say but there is complete likelihood that you will not get correct answer or may be you won't reach any answer! Let us say you are having 2 equations and three unknowns. Maths says you need 3 equations to solve equations having three unknowns. Logic never puts any limitation.
Particularly in case of DI and LR and sometimes in QUANT even, options are to be used inevitably. And sometimes, question become easier if we use options. Let us see one examples to see what wonders options can do:
Question:
Three friends, returning from a movie, stopped to eat at a restaurant Sita took 1/3 of mint but returned 4 because of a momentary pang of guilt. Fatima then took 1/4 of what was left but returned three for similar reason. Eswari then took half of the remainder but threw 2 back to the bowl. Only 17 mints are left now. Determine original number of mints.
options : A)27 B)30 C)48 D)36
Solution: You can always use equations. But process will be time consuming. Let me tell you a logic behind this that CAT wants to check. No one will ever take mind in fractions. they will always take in whole numbers.
If option 1 were true then sita will take 1/3 *27 = 9. Left in bowl = 18. Then she returned 4. So 18 + 4=22 mints were left in bowl. But if 22 are left for fatima and she takes 1/4 *22 then fatima will take 5.5 which is a fraction. Options 1 is eliminated here.
If option 2 were true then sita will take 1/3*30 = 10. Left in bowl = 20. Then she returned 4. So 20+4= 24 mints were left in bowl. Now fatima will take 1/4*24 =6. So mints left in bowl = 18. Then fatima returned 3. So 18+3=21 mints were left in the bowl. Eswari took 1/2 of 21. That is 10.5. Fraction! eliminated!
If option 3 were true then sita will take 1/3*48 = 16. Left in bowl = 32.then she returned 4. So 32+4=36. Now fatima will take 1/4 * 36 =9. So mints left in bowl = 27.Then fatima returned 3. So 3+27 = 30 were left in bowl. Eswari took 1/2 of 30. That is 15. Then Eswari returned 2. That makes 15 + 2 =17. That exactly matches the given data in the question. So our answer is option3.
We need not to look any further option. This process may look long because I have explained it to you. But try to apply this yourself. You will realize that it takes hardly one minute.
Thank you!
We need not to look any further option. This process may look long because I have explained it to you. But try to apply this yourself. You will realize that it takes hardly one minute.
Thank you!
