In an objective paper, there are two sections of 10 questions each.For "section 1", each question has 5 options and only one optionis correct and "sec

Monjur Alahi

In an objective paper, there are two sections of 10 questions each.For "section 1", each question has 5 options and only one optionis correct and "section 2" has 4 options with multiple answers and marks for a question in this section is awarded only if he ticks all correct answers. Marks for each question in "sectionl 1" is 1 and in "section 2" is 3. (There is no negative marking.) If a candidate attempts only two questions by guessing, one from "section 1" and one from "section 2", the probability that he scores in both question is `74/75`
A. `74//75`
B. `1//25`
C. `1//15`
D. `1//75`


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Salim Ahmed Kawsar

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Correct Answer - D
Let `p_(1)` be the probability of being an answer correct from section 1. Then `p_(1)=1//5.` Let `p_(2)` be the probability of being an answer correct from section 2. Then `p_(2)=1//15.` Hence, the required probability is `1//5 xx1//15=1//75.`

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