Question

a student has appeared for an examination there are 20 questions in the paper if he answers correctly he gets 4 marks and if the answer is wrong he gets -1 a student will pass in the examination if he gets 50% of marks if a student answers by sheer guessing then what is the probability that he will pass in the examination?​

Answer 1

Given:

A student has appeared for an examination there are 20 questions in the paper if he answers correctly he gets 4 marks and if the answer is wrong he gets -1.

A student will pass in the examination if he gets 50% of marks.

To find:

If a student answers by sheer guessing then what is the probability that he will pass in the examination?​

Solution:

From given we have,

A total of 20 questions.

4 marks per correct question

-1 mark per wrong question

A student will pass in the examination if he gets 50% of marks.

⇒ 50% × 20

= 50/100 × 20

= 1/2 × 20

= 10

The probability that he will pass in the examination = 10/20 = 1/2 = 0.5