Answer:
64/7 years
9.143 years
Step-by-step explanation:
[tex]Simple Interest = \\ \frac{Principal \times Rate \times Time}{100} [/tex]
[tex]Time = \frac{simple \: interest \times 100}{Principal \times Rate} [/tex]
[tex]Principal = 400 \\ Rate = 14 \\ Time = \\ simple \: interest = 512[/tex]
Input the values
[tex]Time = \frac{512 \times 100}{400 \times 14} \\ Time = \frac{51200}{5600} \\ [/tex]
[tex]Time = \frac{64}{7} \\ Time = 9.142 \: years \\ best \: answer \: = \frac{64}{7} years[/tex]