Question

There are 180 multiple choice questions in a test. A candidate gets 4marks for every correct answer, and for every un attempted or wrongly answered questions one mark is deducted from the total score of correct answers if a candidate scored 450 marks in the test how many questions did he answer correctly

Answer 1

Explanation:

let the number of correctly attempted questions be x

so, the number of unattempeted or wrong question = 180-x

total marks for correct attemptions = 4x

and total marks for unattempeted or wrong question = -1 (180-x)

= x - 180

as total marks = sum of attempted and unattempeted or wrong question = 180-x

450 = 4x + x - 180

450 = 5x -180

630 = 5x

126 = x

so, the number of correctly attempted question was 126.

Answer 2

Explanation:

Let the number of correct questions be x

Wrong questions = 180 - x

Total marks for correct answer = 4x

Total marks for wrong answer = (180-x) * 1

= X - 180

ATQ,

4x + x - 180 = 450

5x = 630

x = 126