In how many years does a sum of money become three times of itself at the rate of $6\frac{1}{4}$ % simple interest per annum?

In how many years does a sum of money become three times of itself at the rate of $6\frac{1}{4}$ % simple interest per annum?
कितने वर्षों में कोई धनराशि $6\frac{1}{4}$ % वार्षिक साधारण ब्याज की दर से अपने आप का तीन गुना हो जाती है?

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