In a class test (+3) marks are given for every correct answer and (-2) marks are given for
every incorrect answer and no marks for not attempting any question.
(i) Radhika scored 20 marks. If she has got 12 correct answers, how many questions has she
attempted incorrectly?
(i) Mohini scores -5 marks in this test, she has got 7 correct answers. How many questions has
she attempted incorrectly?
Answers
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let x = number of marks reduced for wrong answer
let y = number of marks given for correct answer
-2x+3y= total marks
first question
radhika score = 20 marks
correct answers = 12 = y
therefore
-2x+3(12)=20
-2x+36=20
-2x= -16
x=8
she attempted 8 wrong answers
second question
-2x+3y= total marks
-2x+3(7)= -5
-2x+21=-5
-2x=-26
therefore has 12 wrong answers
let y = number of marks given for correct answer
-2x+3y= total marks
first question
radhika score = 20 marks
correct answers = 12 = y
therefore
-2x+3(12)=20
-2x+36=20
-2x= -16
x=8
she attempted 8 wrong answers
second question
-2x+3y= total marks
-2x+3(7)= -5
-2x+21=-5
-2x=-26
therefore has 12 wrong answers
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