Sunday

March 1, 2015

March 1, 2015

Posted by **y912f** on Friday, May 8, 2009 at 5:05pm.

i need to teach this to my brother, but i'm stuck on it myself. please show me how this would be solved

i tried figuring out the area of the whole circle(including the pond and walk) and then subtracting the inner circle (pond)

but i don't get the correct answer

please help

- PreAlgebra -
**RickP**, Friday, May 8, 2009 at 6:33pmYour method should work.

area = 2 * pi * radius^2

area ~ 6.28 * radius^2

POND:

diameter = 20m

radius = diameter / 2

radius = 20m / 2 = 10m

area = 6.28 * (10m)^2 = 6.28 * 100m^2

area = 628m^2

POND and WALK:

remember, the walk goes all the way around the pond, so there is 5m of wall on the west boundary and another 5m of wall on the east boundary. The diameter is increased by 10m, not just 5.

diameter = 20m + 10m = 30m

radius = diameter / 2

radius = 30m / 2 = 15m

area = 6.28 * (15m)^2 = 6.28 * 225m^2

area = 1,413m^2

WALK:

The area of the walk is equal to the area of the pond AND walk minues the area of the pond alone.

area = 1,413m^2 - 628m^2

area = 785m^2

- PreAlgebra -
**Dana**, Monday, February 24, 2014 at 5:20pmNo I don't have an answer so I came to this very unhelpful website. Bye!

**Answer this Question**

**Related Questions**

maths - a circular flower bed is surrounded by a path 3m wide the diameter is ...

Maths - A circular lily pond is surrounded by a gravel walkway that is 4 m wide...

Math - A pond 100 ft in diameter is surrounded by a circular grass walk 2 feet ...

math - a worker in a city park needs to cover a circular path around the outside...

math - A circular pond of diameter 15m is sorrounded by a path of of 2m wide ...

math - a worker in a city parks need to cover a circular path around the outside...

math - A pond 100 feet in diameter is surrounded by a circular grass walk which ...

maths - A rectangular grassyplot is 112m long and 78m broad. It has a gravel ...

Geometry word problem - A rectangular pond is 10m longer than it is wide. A walk...

maths-perimeter - A circular pond has a 95cm wide foot path along the edge.A man...