Percentage


  1. In a quarterly examination a student secured 30% marks and failed by 12 marks. In the same examination another student secured 40% marks and got 28 marks more than minimum marks to pass. The maximum marks in the examination is









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    Maximum marks in the examination = x (let)

    =
    40x
    -
    30x
    = 12 + 28
    100100

    =
    10x
    = 40 ⇒ x = 40 × 10 = 400
    100

    Aliter : Using Rule 22,
    Here, m = 30%, n = 40%, p = 12, q = 28
    ∴ Maximum marks
    =
    100
    × (p + q)
    (n - m)

    =
    100
    × (12 + 28)
    (40 - 30)

    =
    100 × 40
    = 400
    10

    Correct Option: D

    Maximum marks in the examination = x (let)

    =
    40x
    -
    30x
    = 12 + 28
    100100

    =
    10x
    = 40 ⇒ x = 40 × 10 = 400
    100

    Aliter : Using Rule 22,
    Here, m = 30%, n = 40%, p = 12, q = 28
    ∴ Maximum marks
    =
    100
    × (p + q)
    (n - m)

    =
    100
    × (12 + 28)
    (40 - 30)

    =
    100 × 40
    = 400
    10


  1. In an examination there are three subjects of 100 marks each. A student scores 60% in the first subject and 80% in the second subject. He scored 70% in aggregate. His percentage of marks in the third subject is









  1. View Hint View Answer Discuss in Forum

    Total marks scored in all three subjects

    =
    300 × 70
    = 210
    100

    ∴ Marks scored in third subject
    = 210 – 60 – 80 = 70

    Correct Option: D

    Total marks scored in all three subjects

    =
    300 × 70
    = 210
    100

    ∴ Marks scored in third subject
    = 210 – 60 – 80 = 70



  1. In an examination, a student must get 36% marks to pass. A student who gets 190 marks failed by 35 marks. The total marks in that examination is









  1. View Hint View Answer Discuss in Forum

    Let total marks in the exam be x.
    According to the question,

    =
    x × 36
    = 190 + 35 = 225
    100

    ⇒ x × 36 = 225 × 100
    ⇒ x =
    225 × 100
    = 625
    36

    Aliter : Using Rule 24,
    a = 36%, b = 190, c = 35
    Total marks =
    (b + c) × 100
    a

    =
    (190 + 35) × 100
    36

    =
    225 × 100
    = 625
    36

    Correct Option: D

    Let total marks in the exam be x.
    According to the question,

    =
    x × 36
    = 190 + 35 = 225
    100

    ⇒ x × 36 = 225 × 100
    ⇒ x =
    225 × 100
    = 625
    36

    Aliter : Using Rule 24,
    a = 36%, b = 190, c = 35
    Total marks =
    (b + c) × 100
    a

    =
    (190 + 35) × 100
    36

    =
    225 × 100
    = 625
    36


  1. A candidate who gest 20% marks in an examination, fails by 30 marks. But if he gets 32% marks, he gets 42 marks more than the minimum pass marks. Find the pass percentage of marks.









  1. View Hint View Answer Discuss in Forum

    Let the full marks of exam be x.
    According to the question,

    =
    x × 32
    -
    x × 20
    = 30 + 42
    100100

    =
    12x
    = 72
    100

    ⇒ x =
    72 × 100
    = 600
    12

    ∴ Minimum marks to pass
    ⇒ x =
    600 × 20
    + 30 = 120 + 30 = 150
    100

    ∴ Required percentage
    =
    150
    × 100 = 25%
    600

    Aliter : Using Rule 22,
    Here, m = 20%, n = 32%, p = 30 and q = 42
    Full Marks =
    100
    × (p + q)
    (n - m)

    =
    100
    × (30 + 42)
    (32 - 20)

    =
    100 × 72
    = 600
    12

    ∴ Passing Marks = 20% of 600 + 30
    =
    20 × 600
    + 30 = 120 + 30 = 150
    100

    ∴ Pass percentage =
    150
    × 100 = 25%
    600

    Correct Option: C

    Let the full marks of exam be x.
    According to the question,

    =
    x × 32
    -
    x × 20
    = 30 + 42
    100100

    =
    12x
    = 72
    100

    ⇒ x =
    72 × 100
    = 600
    12

    ∴ Minimum marks to pass
    ⇒ x =
    600 × 20
    + 30 = 120 + 30 = 150
    100

    ∴ Required percentage
    =
    150
    × 100 = 25%
    600

    Aliter : Using Rule 22,
    Here, m = 20%, n = 32%, p = 30 and q = 42
    Full Marks =
    100
    × (p + q)
    (n - m)

    =
    100
    × (30 + 42)
    (32 - 20)

    =
    100 × 72
    = 600
    12

    ∴ Passing Marks = 20% of 600 + 30
    =
    20 × 600
    + 30 = 120 + 30 = 150
    100

    ∴ Pass percentage =
    150
    × 100 = 25%
    600



  1. If the income tax is increased by 19%, the net income is reduced by 1%. The rate of income tax is









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    Let the income be ₹x and the rate of income tax be y %
    According to the question,

    xy × 1.19
    -
    xy
    100100

    = x -
    xy
    ×
    1
    100100

    ⇒ 1.19 xy – xy = x -
    xy
    100

    ⇒ 1.19y = 1 -
    y
    100

    y
    + 1.19y = 1
    100

    ⇒ y
    1 + 19
    = 1
    100

    ⇒ y =
    100
    = 5%
    20

    Correct Option: C

    Let the income be ₹x and the rate of income tax be y %
    According to the question,

    xy × 1.19
    -
    xy
    100100

    = x -
    xy
    ×
    1
    100100

    ⇒ 1.19 xy – xy = x -
    xy
    100

    ⇒ 1.19y = 1 -
    y
    100

    y
    + 1.19y = 1
    100

    ⇒ y
    1 + 19
    = 1
    100

    ⇒ y =
    100
    = 5%
    20