If a sum of money at simple interest doubles in 6 years, it will become 4 times in Choose the correct choice.
A) 15years B) 16years C) 11years D) 18years E) 12years
Explanation:   let sum =x . s.i.=x   rate =(100*x)/(x*6)=50/3%   now ,sum =x, s.i= 3x, rate =50/3%   time =(100*3x)/(x*50/3) = 18 years   Answer: 18years
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If a sum of money at simple interest doubles in 6 years, it will become 4 times in