7. In an entrance exam consisting of 30 questions, 4 marks are given for every correct answer and
2 marks are deducted for every incorrect answer while no marks are deducted for the questions that are not attempted
a. Aarushi scored 60 marks by answering 20 questions correctly. If she had attempted all the questions find the number of incorrect answer.
b. Ajay scored 48 marks by answering 15 questions correctly. Find the number of questions not attempted by him.
please give me step by step
Answers
Answered by
3
Step-by-step explanation:
a) Given:
Marks scored by Aarushi= 60 marks
Total no. of questions = 30
No. of correct answer = 20
She attempted all questions.
Let, no. of incorrect answers be x.
20 + x = 30
x = 30 - 20
x = 10
Therefore,
No. of incorrect answers are 10.
b) Total no. of questions in exam = 30
Total marks scored by Ajay = 48 marks
No. of correct answer = 15
Marks scored by correct answer = 4 x 15 = 60 marks
Marks deducted by incorrect answer = 60 - 48 = 12 marks
Therefore, no. of incorrect answers = Marks deducted by incorrect answer/ Marks deducted for every incorrect answer
= 12/2 = 6
Let the no. of questions not attempted by him be x.
15 + 6 + x = 30
21 + x = 30
x = 30 - 21
x = 9
Hence, 9 questions not attempted by Ajay.
Similar questions