Question

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

Answer 1

4x is +ve marks
180-x is -ve marks
therefore,
4x -(180-x)=450
this gives x=126 correctly answered questions

Answer 2

Hi friend!

$<marquee direction="right" behavior="alternate"><big><big><b>Answer:</b></big></big></marquee>$

Total questions = 180
Correct answer = x
Remaining - Unattempted + Wrong answers = 180 - x

Points for each correct answer = 4
Points for all the correct answers = 4x

Points for each wrong and unattempted answer = -1
Points for all unattempted and wrong answers = -1(180 - x) = -180 + x

Total points
$= 450 = 4x - 180 + x \\ \\ 5x - 180 = 450 \\ 5x = 450 + 180 = 630 \\ x = \frac{630}{5} \\ \\ x = 126$

$No. of correct answers = x = <b><big>126</big></b>. No. of wrong and unattempted answers = 180 - x = 180 - 126 = <b>54</b>.$

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