astro turf

Bob’s Prob

Bob the gardener had a circular garden and all he knew was that it had a radius of 2.8m.

Bob had to line the edge garden with bricks that were 10cm wide and fill in the garden with astro turf.

Lots And Lots Of Bricks First Bob had to find out what the

circumference of the garden is.

Lots And Lots Of Bricks But all bob knows is that the radius of the

garden is 2.8 meters.

2.8 m

Lots And Lots Of Bricks Bob being smart one, uses the formula

2 x Pi x (r) 280cm

Lots And Lots Of Bricks So Bob puts that formula into his calculator

2 x Pi x 280

%

1 2 3 4 5 6 7

8 9 0 x + /

=Pi - . ( ) abc

Lots And Lots Of Bricks Which equals 1759

1759

%

1 2 3 4 5 6 7

8 9 0 x + /

=Pi - . ( ) abc

Lots And Lots Of Bricks Then he divides it by 10cm because that is

how wide the bricks are.

/10

%

1 2 3 4 5 6 7

8 9 0 x + /

=Pi - . ( ) abc

Lots And Lots Of Bricks Which equals 175.9, and that is how many bricks

Bob estimates he will need to edge the garden.

175.9

%

1 2 3 4 5 6 7

8 9 0 x + /

=Pi - . ( ) abc

Astro turf Bob needs to find out how much astro

turf he needs. He uses a method called the corner square method.

Astro turf

Bob finds the area by times the radius by the radius to create a square.

2.8m

2.8m

Astro turf

Then you times it by pi (3.14)

2.8m

2.8m

Astro turfSo Bob put in to his calculator, 2.8 x 2.8 x Pi

2.8 x 2.8 x pi

%

1 2 3 4 5 6 7

8 9 0 x + /

=Pi - . ( ) abc

Astro turfWhich ends up equaling to 24.63 m2 which is

how much astro turf Bob needs.

24.63

%

1 2 3 4 5 6 7

8 9 0 x + /

=Pi - . ( ) abc

Bob’s Prob is Fixed

So now Bob knows how much bricks and turf he needs to complete the garden.

175 Brick and 24.63 m2 of turf