logo

CuriousTab

CuriousTab

Discussion


Home Aptitude Volume and Surface Area Comments

  • Question
  • What is the percentage decrease in the area of a triangle if its each side is halved?


  • Options
  • A. 75%
  • B. 50%
  • C. 25%
  • D. No change

  • Correct Answer
  • 75% 

    Explanation
    Area of triangle of = ½*a*b* sin? = A
    Where a and b are sides of the triangle and ? be the angle between them
    After decreasing each side
    New area = ½*(a/2)*(b/2)*sin? = ¼ A
    %decrease = [(A?¼ A)/A ]*100 = 75%
  • Tags: Bank Exams

    Volume and Surface Area problems


    Search Results


    • 1. Consider the following statements: 1) The perimeter of a triangle is greater than the sum of its three medinas. 2) In any triangle ABC, if D is any point on BC, then AB + BC + CA > 2AD. Which of the above statements is/are correct?

    • Options
    • A. 1 only
    • B. 2 only
    • C. Both 1 and 2
    • D. Neither 1 nor 2
    • Discuss
    • 2. In a circle of radius 8 cm, AB and AC are two chords such that AB = AC = 12 cm. What is the length of chord BC?

    • Options
    • A. 2?6 cm
    • B. 3?6 cm
    • C. 3?7 cm
    • D. 6?7 cm
    • Discuss
    • 3. ABCD is a quadrilateral with AB = 9 cm, BC = 40 cm, CD = 28 cm, DA = 15 cm and angle ABC is a right ?angel. What is the area of triangle ADC?

    • Options
    • A. 126 SQ.CM
    • B. 124 SQ.CM
    • C. 122 SQ.CM
    • D. 120 SQ.CM
    • Discuss
    • 4. In ?PQR, ?QPR = 45° and the bisectors of ?PQR and ?PRQ meets at O. What is the value (in degrees) of ?QOR?

    • Options
    • A. 107.5
    • B. 112.5
    • C. 117.5
    • D. 122.5
    • Discuss
    • 5. A solid sphere of diameter 7 cm is cut into two equal halves. What will be the increase (in cm2) in the total surface area ?

    • Options
    • A. 77
    • B. 154
    • C. 87
    • D. 38.5
    • Discuss
    • 6. If the lengths of two parallel chords in a circle of radius 10 cm are 12 cm and 16 cm, then what is the distance between these two chords?

    • Options
    • A. 1 cm or 7 cm
    • B. 2 cm or 14 cm
    • C. 3 cm or 21 cm
    • D. 4 cm or 28 cm
    • Discuss
    • 7. The co-ordinates of the centroid of a triangle ABC are (-1 , 4). What are the co-ordinates of vertex C if co-ordinates of A and B are (-3 , -1) and (3 , 5) respectively?

    • Options
    • A. (-3 , 8)
    • B. (3 , 8)
    • C. (-3 , -8)
    • D. (3 , -8)
    • Discuss
    • 8. What is the reflection of the point (-4, 3) in the line x = -2?

    • Options
    • A. (-4 , -7)
    • B. (4 , 3)
    • C. (0 , 3)
    • D. (-4 , 7)
    • Discuss
    • 9. ?XYZ is similar to ?PQR. If ratio of Perimeter of ?XYZ and Perimeter of ?PQR is 4:9 and if PQ = 27 cm, then what is the length of XY (in cm)?

    • Options
    • A. 9
    • B. 12
    • C. 16
    • D. 15
    • Discuss
    • 10. The surface area of a sphere is 5544 sq.cm. Find its diameter (in cm).

    • Options
    • A. 42
    • B. 21
    • C. 84
    • D. 63
    • Discuss


    Comments

    There are no comments.

Enter a new Comment