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Question
So Anar also tried many different ways to make a boundary for 800 square meters of land.
He made rectangles A, B, and C of different sizes. Find out the length of the boundary of each. How much gold wire will he get for these rectangles?
- A
Gold wire for A = _________ metres - B
Gold wire for B = _________ metres - C
Gold wire for C = __________ metres
But then Anar made an even longer rectangle... See how long!
- D
So he will get __________ metres of gold wire!!
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Solution
Area of 30 m × 20 m rectangle = 600 square metres
Its area is larger than the area of the first rectangle.
The other rectangles that he can make with 100 metres of wire are
40 m × 10 m,
48 m × 2 m,
49 m × 1 m,
45 m × 5 m
- A
As the area of a rectangle, A is shown as 40 m × 20 m.
So, the length of rectangle = 40 m
Width of rectangle = 20 m
Gold wire for A
= 40 + 20 + 40 + 20
= 120 metres - B
As the area of rectangle B is shown as 80 m × 10 m.
So, the length of rectangle = 80 m
Width of rectangle = 10 m
Gold wire for B
= 80 + 10 + 80 + 10
= 180 metres - C
As the area of rectangle C is shown as 800 m × 1 m.
So, the length of rectangle = 800 m
Width of rectangle = 1 m
Gold wire for C
= 800 + 1 + 800 + 1
= 1602 metres - D
As the area of rectangle D is shown as 8000 m × 0.1 m.
So, the length of rectangle = 8000 m
Width of rectangle = 0.1 m
Gold wire for C
= 8000 + 0.1 + 8000 + 0.1
= 16000 + 0.2
= 16000.2 metres.
So, he will get 16000.2 metres of gold wire!!
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