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 By: sundarshoba (offline)  Sunday, July 08 2012 @ 05:46 PM CDT (Read 840 times)
sundarshoba

Please help to check the question 15 as attached, thank you very much

Chatty

Registered: 12/31/06
Posts: 53

 By: echeewh (offline)  Sunday, July 08 2012 @ 11:50 PM CDT
echeewh

Hey Sundar,

Answer is (b) 62.8 cm.

Here's how .....

Join centre O to top edge of circle where the right angle is. This makes it the radius of the circle.

Hence, 1/2 the given triangle = 50 cm2.

Area of this half triangle = (r x r) / 2 = 50
r x r = 100
r = 10 cm

Circumference of circle = 2 x pi x r = 20 x 3.14
= 62.8 cm

=============

Trust this helps.

Cheers,
Edward

Active Member

Registered: 04/21/11
Posts: 627

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