Question 5 Recently, the answers of a test held nationwide were leaked to a group of unscrupulous people. The investigative agency has arrested the mastermind and nine other people A, B, C, D, E, F, G, H, and I in this matter. Interrogating them, the following facts have been obtained regarding their operation. Initially the mastermind obtains the correct answer-key. All the others create their answer-keys in the following manner. They obtain the answer key from one or two people who already possess the same. These people are called his/her "sources". If the person has two sources, then he/she compares the answer keys obtained from both sources. If the key to a question from both sources is identical, it is copied, otherwise it is left blank. If the person has only one source, he/she copies the source's answers into his/her copy. Finally, each person compulsorily replaces one of the answers (not a blank one) with a wrong answer in his/her answer key. The paper contained 200 questions; so the investigative agency has ruled out the possibility of two or more of them introducing wrong answers to the same question. The investigative agency has a copy of the correct answer key and has tabulated the following data. These data represent question numbers.
Name
Wrong Answers
Blank Answers
A
46
-
B
96
46,90,25
C
27,56
17,46,90
D
17
-
E
46,90
-
F
14,46
92,90
G
25
-
H
46,92
-
I
27
17,46,90
1) Which one among the following must have two sources?
a. A b. B c. C d. D (adsbygoogle = window.adsbygoogle || []).push({});
2) How many people (excluding the mastermind) needed to make answer-keys before C could make his answer-key?
a. 2 b. 3 c. 4 d. 5
3) Both G and H were sources to
a. F b. B c. 1 d. None of the nine
4) Which of the following statements is true?
a. C introduced the wrong answer to question 27.b. E introduced the wrong answer to question 46.c. F introduced the wrong answer to question 14.d. H introduced the wrong answer to question 46.
5) Which of the following two groups of people had identical sources?
(1) A, D and G
(2) E and H
a. Only (1)b. Only (2)c. Neither (1) nor (2)d. Both (1) and (2) (CAT 2003)
