16. A problem of mathematics is given to three students whose chances of solving the problem are 1/3, 1/4 & 1/5 respectively. The probability that the question will be solved is :
(a) 2/3
(b) 3/4
(c) 4/5
(d) 3/5
17. A speaks truth in 75% cases and B in 80% cases. In what % of cases are they likely to contradict each other in stating the same fact.
(a) 5 %
(b) 55 %
(c) 35 %
(d) 45 %
18. Six boys and six girls sit in a row. What is the probability that the boys and girls sit alternatively.
(a) 1/462
(b) 1/924
(c) 1/2
(d) none of these
19. A man and a woman appear in an interview for 2 vacancies in the same post. The prob. of man’s selection is 1/4 and that of woman’s selection is 1/3. What is the probability that none of them will be selected ?
(a) 1/2
(b) 1/12
(c) 1/4
(d) none of these
20. 3 dice are thrown simultaneously. What is the probability of obtaining a total of 17 or 18 ?
(a) 1/9
(b) 1/72
(c) 1/54
(d) none of these
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