SOLUTION: THE AMOUNT OF A RADIOACTIVE TRACER REMAINING AFTER t DAYS IS GIVEN BY A=Aoe^0.18t, WHERE Ao IS THE STARTING AMOUNT AT THE BEGINNING OF THE TIME PERIOD. HOW MUCH SHOULD BE ACQUIRED

Question 64133: THE AMOUNT OF A RADIOACTIVE TRACER REMAINING AFTER t DAYS IS GIVEN BY A=Aoe^0.18t, WHERE Ao IS THE STARTING AMOUNT AT THE BEGINNING OF THE TIME PERIOD. HOW MUCH SHOULD BE ACQUIRED NOW TO HAVE 40 GRAMS REMAINING AFTER 3 DAYS?
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
THE AMOUNT OF A RADIOACTIVE TRACER REMAINING AFTER t DAYS IS GIVEN BY A=Aoe^0.18t, WHERE Ao IS THE STARTING AMOUNT AT THE BEGINNING OF THE TIME PERIOD. HOW MUCH SHOULD BE ACQUIRED NOW TO HAVE 40 GRAMS REMAINING AFTER 3 DAYS?
:
I think the equation should be: A = Ao(e^-.18t)

Substitute 40 for A, and 3 for t, solve for Ao:
Ao*(e^-.18(3)) = 40
:
Ao*(e^-.54) = 40
:
On a good calc find e^.-54
Ao * .5827 = 40
Ao = 40/.5827
Ao = 68.64 grams

RELATED QUESTIONS
The amount of a radioactive tracer remaining after t days is given by A=Aoe^-0.058t,... (answered by ankor@dixie-net.com)

the amount of radioactive tracer remaining after t days is given by A=Aoe^(-0.058t),... (answered by adamchapman)

the amount of a radioactive tracer remaining after t days is given by A=Ao e^(-0.18t),... (answered by adamchapman)

The amount of a radioactive tracer remaining after t days is given by A=Ao e^-0.18t,... (answered by stanbon)

HELP???? The amount of a radioactive tracer remaining after t days is given by A = Ao... (answered by Nate)

PLEASE HELP ME: The amount of a radioactive tracer remaining after t days is given by... (answered by funmath)

THE AMOUNT OF A RADIOACTIVE TRACER REMAINING AFTER t DAYS IS GIVEN BY A=Ao e-0.058t,... (answered by venugopalramana)

The amount of radioactive tracer remaining after t days is given by A =Ao e-o.o58t, where (answered by bucky,jim_thompson5910)

I really need help with this one. I am trying to plug in numbers and i am not getting it. (answered by stanbon)