Solve the problem.
-There are currently 57 million cars in a certain country, increasing by $7.5 \%$ annually. How many years will it take for this country to have 85 million cars? Round to the nearest year.
A) $3 \mathrm { yr }$
B) $4 \mathrm { yr }$
C) $44 \mathrm { yr }$
D) $5 \mathrm { yr }$

Question

Quizplus · Accepted Answer

To find the number of years it will take for the car population to grow from 57 million to 85 million with an annual increase of 7.5%, we can use the formula for exponential growth: $P = P_0(1 + r)^t$, where $P$ is the future value, $P_0$ is the initial value, $r$ is the rate of increase, and $t$ is the time in years. Plugging in the values, we get $85 = 57(1 + 0.075)^t$. Solving for $t$, we find that it takes approximately 5 years to reach 85 million cars.

Solve the Problem 7.5%7.5 \%7.5% Annually How Many Years Will It Take for This Country

Solve the Problem $7.5 \%$ Annually How Many Years Will It Take for This Country