if three 1 rupee coin can be placed around a 10 paise coins such that each one rupee coin touches the 10 paise coin as well as the other 1 rupees coins, the ratio of the radii of 1 rupee and 10 paise coin is:

Explanation

Let `R` is the radius of 1 rupee coin and `r` is the radius of 10 paise coin.

Let `C_1, C_2, C_3` are the center of each one rupee coin and `C'` is the center of 10 paise coin.
Then, `Delta C_1C_2C_3` will be an equilateral triangle with each angle `60^@`.

Please refer to video for the diagram.

From the diagram, we can see that,

`C'C_1 = r+R`

`OC_1 = R`

In `Delta OC_1C'`,

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