In an objective test, a correct answer scores 4 marks, and a wrong answer scores 2 marks. A student scores 480 marks from 150 questions. how many answers are correct?

• if all ans. right the marks=4*150=600
  but score=480
  wrong attempt marks=600-480=120
  wrong ans.=120/2=60
  right ans.=150-60=90.
• 11 years agoHelpfull: Yes(47) No(15)
• x+y=150
  4x+2y=480
  
  so x=90 and y=60
  correct answer =90
• 11 years agoHelpfull: Yes(24) No(16)
• 130 right 20 wrong...
• 11 years agoHelpfull: Yes(22) No(16)
• if all ans. right the marks=4*150=600
  but score=480
  wrong attempt marks=600-480=120
  wrong ans.=120/2=60
  right ans.=150-60=90.
• 11 years agoHelpfull: Yes(10) No(8)
• total marks if each answer is correct=600
  but one obtains=480 (60%)
  find 60% of 150 = 90
  
• 11 years agoHelpfull: Yes(6) No(5)
• student score 480 marks from 150 questions...
  if student give 130 right answer then 130*4=520
  and 20 wrong answer then 20*2=40
  then the score will be 520-40=480
  then 130 ans will be correct
  
  
• 10 years agoHelpfull: Yes(4) No(1)
• right answer 4marks-480 attempt que-120
  wrong answer 2marks-60 attempt que-30
  so answer is-135 right 15 wrong
• 11 years agoHelpfull: Yes(2) No(9)
• sorry prime no is 229 & 233
• 10 years agoHelpfull: Yes(1) No(2)
• x=60 n y=90
  let no of ques he attempts correctly be x
  and no of wrong ques be y
  then x+y=150
  4x+2y=480
• 10 years agoHelpfull: Yes(0) No(0)
• Let the numbers be x, x+1, x+2, x+3, x+4, x+5, x+6
  Since their sum equals 1617, we have-
  x+(x+1)+(x+2)+(x+3)+(x+4)+(x+5)+(x+6)=1617
  7x+21=1617
  7x=1596
  x=228
  
  Hence the numbers are: 228,229,230,231,232,233,234
  Prime Numbers: 229, 231,233
• 10 years agoHelpfull: Yes(0) No(0)
• 90 question`s answers are correct = 90*4 = 360 marks
  60 question`s answers are wrong = 60*2 = 120 marks
  and Total Marks = 360+120 = 480 Marks
  
  90 correct answers
• 10 years agoHelpfull: Yes(0) No(0)
• answer 130
  max marks=600(150*4)
  marks obtained=480
  so 120 marks less than total marks.
  thus if she had done 20 question wrongly then she will loose 6 marks per question totaling to 120
  hence correctly answered ques 150-20=130
• 6 years agoHelpfull: Yes(0) No(0)