Please help me with a Rate Law problem.?

Okay I've spent nearly an hour on this problem with no luck, please help me and explain how you do this. A reaction of the form aA ----> Product gives a plot of ln[A] vs time in seconds which is a straight line with a slope of -7.35 x10^-3. Assuming 0.0100 M, calculate the time in seconds required for... show more Okay I've spent nearly an hour on this problem with no luck, please help me and explain how you do this.

A reaction of the form

aA ----> Product gives a plot of ln[A] vs time in seconds which is a straight line with a slope of -7.35 x10^-3. Assuming 0.0100 M, calculate the time in seconds required for the reaction to reach 80.5 percent completion.

I have the integrated rate law as ln[A]= -kt + ln[A]_0. but it's not getting be the right answer. Please help.
3 answers 3