πŸ“’ Too many exams? Don’t know which one suits you best? Book Your Free Expert πŸ‘‰ call Now!

  • google app store apple app store
  • βœ–

      Question

      Length of a chord in a circle of radius 'r' cm, is 40 cm

      and distance between chord and centre of the circle is 21 cm. Find the value of (2r + 1).
      A 55 Correct Answer Incorrect Answer
      B 59 Correct Answer Incorrect Answer
      C 61 Correct Answer Incorrect Answer
      D 63 Correct Answer Incorrect Answer

      Solution

      Image
      AB is the chord of circle.
      Perpendicular line joining the centre of circle and chord, bisects the chord.
      i.e. AC = BC = (40/2) = 20 cm
      By Pythagoras theorem,
      OA 2 = OC 2 + AC 2
      Or, r 2 = 21 2 + 20 2
      Or, r 2 = 441 + 400
      Or, r 2 = 841
      So, 'r' = 29
      But length cannot be negative. So, 'r' = 29
      Required value = 2 X 29 + 1 = 59

      Practice Next
      ask-question