Area and Perimeter


  1. The area of a right angled triangle is 40 sq cm. If its base is equal to 28 cm. find its height.











  1. View Hint View Answer Discuss in Forum

    Given that,
    area = 40 sq cm,
    base = 28 cm and
    height = perpendicular = ?

    Area = (base x perpendicular) / 2

    Correct Option: C

    Given that,
    area = 40 sq cm,
    base = 28 cm and
    height = perpendicular = ?

    Area = (base x perpendicular) / 2
    ⇒ 40 = (28 x perpendicular) / 2
    ∴ perpendicular = 40/14 = 20/7
    = 26/7 cm


  1. The area of a right angled triangle is 10 sq cm. If its perpendicular is equal to 20 cm, find its base.











  1. View Hint View Answer Discuss in Forum

    Given that, area = 10 sq cm,
    perpendicular = 20 cm and base = ?
    area = (base x perpendicular) / 2

    Correct Option: A

    Given that, area = 10 sq cm,
    perpendicular = 20 cm and base = ?
    area = (base x Perpendicular) / 2
    ⇒ 10 = (base x 20) / 2
    ∴ base = 1 cm



  1. What is the diameter of the circle having 3 cm radius?











  1. View Hint View Answer Discuss in Forum

    Radius = Diameter/2
    ∴ Diameter = 2 x Radius

    Correct Option: A

    Radius = Diameter/2
    ∴ Diameter = 2 x Radius
    = 2 x 3
    = 6 cm


  1. If the sides of a rectangle are increased by 10% find the percentage increased in its diagonals.









  1. View Hint View Answer Discuss in Forum

    According to the formula,
    ∵ Percentage increase in sides = 10%
    ∴ Percentage increase diagonals = 10%

    Correct Option: B

    According to the formula,
    ∵ Percentage increase in sides = 10%
    ∴ Percentage increase diagonals = 10%



  1. If the sides of a rectangle are increased by 5%, find the percentage increase in its diagonals.











  1. View Hint View Answer Discuss in Forum

    According to the formula,
    Percentage increase in diagonals = 5%

    Correct Option: C

    According to the formula,
    Percentage increase in diagonals = 5%