i think its D but not 100% sure
Nvm i found the answer i'll explain.. :p
if the radius of the circle = r. Then the side of the large square will be X and the side of the little square be x. (0.5X)2 + (0.5X)2 = r2 = 2*0.25X2 = 0.5X2. X2 = 2r2. (0.5x)2 + x2 = r2. 1.25x2 = r2. x2 = 0.8r2. x2:X2 = 0.8r2 : 2X2 = 2:5.
Mitch, 18. Leeds University in September
The answer is B
- The square in a half circle / The square in the full circle
- Half of the circle is 0.5, the smaller square is at a ratio of 0.5
Answer: 1:2
The answer is C, 2:5
The small square:
r is the radius of the circle
Finding angle θ:
tan θ = 2/1
θ = tanֿ¹ 2
θ = 63.4º (3sf)
Finding the length 2a in terms of r:
sin 63.4 = 2a / r
2a = r sin 63.4
2a = 0.894 r
Area of square:
Area = (0.894 r)²
Area = 0.8 r²
The big square:
Finding b in terms of r:
sin 45 = b / r
b = r sin 45
b = 0.707 r
therefore 2b = 1.41 r
Area of square:
Area = (1.41 r)²
Area = 2 r²
So, the ratio is 0.8:2
= 2:5
Last edited by Jesus-Egg; 09-02-2007 at 06:45 PM.
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