Question
An amount becomes six times of itself in 50 years at
simple interest. Find the value of (2R + 30).Solution
Let the amount invested be Rs. 'p'.
Interest earned = 6p − p = Rs. 5p
Simple interest = Principal × Rate × Time ÷ 100
So, 5p = p × R × 50 ÷ 100
Or, R = (5 × 100) ÷ 50 = 10
Required value = 2 × 10 + 30 = 20 + 30 = 50
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