A certain amount is lent at x p a simple interest for 3 years Instead if the amount was lent at 3x p...........

Quantitative Aptitude (CGL) Simple Interest

A certain amount is lent at x% p.a. simple interest for 3 years. Instead, if the amount was lent at 3x% p.a. simple interest for ‘y’ more years, then the simple interest would have been seven times the earlier interest. What is the value of y?

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