Problem of this day
Find the radius of the smaller circle.
Note by
Indulal Gopal
7 years, 8 months ago
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19 votes
Easy Math Editor
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Using Basic proportionality theorem 12r=2012⇒r=20144=7.2
Once you find the like triangles it's not that hard anymore :)
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exactly
I converted it into a problem of Straight Lines. Mapping the distance of the centre of a sphere from the topmost point on the y axis , and radius on the x axis, I calculated slope by calculating dy/dx of the given 2 spheres as (52-20)/(12-20) = -4 . Then using the equation of straight line y=mx+c and putting the value of y=52 and x=12, 52=(-4)x12 +c, c comes out to be 100. Then for the unknown radius , we know y=64+r and x=r. Solving this 64+r=(-4) x r +100 which gives r=7.2........ Cool approach, isn't it?
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but just have a little hard to understand your formula...
r = 7.2cm
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Salman , I think you made an error. Its not 5 cm. Think and do. You can solve it
N ths is a prblm -_- Simply,36/5 gives 7.2
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Where'd you get 36 and 5?
1.2
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Nope :)
7.2 cm.
7.2 cm
The answer is not 7.2?
radius is 7.2cm
...Well... 2012=12x⇒x=536. Waaay too simple.
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but how do you get 36/5 ?
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From above we can get x=20144=536
7.2
7.2 cm
7.2
7.2cm?? or 4.0cm??
7.2 cm
7.2 cm
7.2 cm...
7.2 cm
I think the proper answer is 7.2cm if I no mistaken...
7.2
3
7.2 cm
7.2
It is too easy to be the problem of the day .r=7.2cm
7.2
use basic proportionality theorem r/12=12/20 r=7.2
This problem can be resolved by using Geometric progression. The rays are in G.P. . So 20/12=5/3 it's the common ratio. 12/5/3= 7,2=r
Similar triangles
7.2 cm
20/12=12/r r=7.2
4
72
7.2 cm
Just basic proportionality funda and you are through. r/12=12/20 r=7.2cm
20:12 = 5:3 12:r = 5:3 r = 3:5 x 12 r = 7,2 what a simple
Is the answer 4.8?
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No, it's not.