SOLUTION: there are currently 71 million cars in a certain county, decreasing by 1.5% annually how many years will it take for this country to have 42 million cars

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Question 1077756: there are currently 71 million cars in a certain county, decreasing by 1.5% annually how many years will it take for this country to have 42 million cars
Found 3 solutions by Boreal, amfagge92, MathTherapy:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
42=71(1-0.015)^t
42/71=.985^t
.5915=.985^t
ln both sides
-.5250=tln (.985)=t*(-0.0151)
t=34.77 years

Answer by amfagge92(93) About Me  (Show Source):
You can put this solution on YOUR website!
71*1.5/100=1.065 approx 1M
time to reach 42
X* 1=42
42 years.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

there are currently 71 million cars in a certain county, decreasing by 1.5% annually how many years will it take for this country to have 42 million cars
Correct answer: , which is a little less than 35 years.