A sum of money doubles itself on simple interest in 10 years. Find the rate of interest per annum.
Explanation
Step 1: Define the Variables
Let:
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P = Principal amount
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R = Rate of interest per annum
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T = Time in years = 10 years
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A = Amount after 10 years
According to the question, the sum of money doubles itself:
Step 2: Calculate Simple Interest (SI)
The Simple Interest is the difference between the Amount and the Principal:
Step 3: Apply the Simple Interest Formula
The formula for Simple Interest is:
Substitute the values SI=P and T=10:
Step 4: Solve for R
Divide both sides by P:
Final Answer
The rate of interest per annum is 10%.