8th Class Mathematics Related to Competitive Exam Question Bank Arithmetic

  • question_answer
    A candidate who gets 30% of the marks in an examination fails by 50 marks. Another candidate who gets 320 marks fails by 30 marks. Then the maximum marks is

    A) 800         

    B) 900

    C) 1,000                    

    D) 1,100

    Correct Answer: A

    Solution :

    Let the full marks = x First candidates gets 30% of x in exam i.e., he gets \[\frac{a}{b}=\left( \frac{a}{b}\times 100 \right)%\] marks m the exam Now, another candidate gets 320 marks and fails by 30 marks. \[\text{Percentage increase=}\left( \frac{\text{Increase in quantity}}{\text{Original quantity}}\text{ }\!\!\times\!\!\text{ 100} \right)\text{ }\!\!%\!\!\text{ }\] Passing marks \[\text{Percentage decrease =}\left( \frac{\text{Decrease in quantity}}{\text{Original quantity}}\text{ }\!\!\times\!\!\text{ 100} \right)\text{ }\!\!%\!\!\text{ }\] Now, first candidate fails by 50 marks \[\left\{ \frac{x}{(100+x)}\times 100 \right\}%\] Passing marks for him \[\left\{ \frac{x}{(100-x)}\times 100 \right\}%\] But he gets \[=\left\{ \left( \frac{r}{r+100} \right)\times 100 \right\}%\] marks \[=\left\{ \left( \frac{r}{r-100} \right)\times 100 \right\}%\]  \[S.P.-C.P\] \[S.P.\text{ }>\text{ }C.P.\] \[C.P.-S.P\] \[C.P.\text{ }>\text{ }S.P.\]          Maximum marks = 800.         


You need to login to perform this action.
You will be redirected in 3 sec spinner