Question

Assume that a company sold 5.75 million motorcycles and 3.5 million cars in the year 2010. The growth in the sale of motorcycles is 16% every year and that of cars is 25% every year. Find when the sale of cars will be more then the sale of motorcycles.

Answer 1

Answer:

Final answer is approx 6.644 years.

Step-by-step explanation:

Given that a company sold 5.75 million motorcycles and 3.5 million cars in the year 2010. The growth in the sale of motorcycles is 16% every year and that of cars is 25% every year.

So we can use growth formula:

$A=P\left(1+r\right)^t$

Then we get equation for motorcycles and cars as:

$A=5.75\left(1+0.16\right)^t$

$A=3.5\left(1+0.25\right)^t$

Now we need to find about when the sale of cars will be more than the sale of motorcycles. So we get:

$3.5\left(1+0.25\right)^t>5.75\left(1+0.16\right)^t$

$3.5\left(1.25\right)^t>5.75\left(1.16\right)^t$

$3.5\left(1.25\right)^t>5.75\left(1.16\right)^t$

$\frac{\left(1.25\right)^t}{\left(1.16\right)^t}>\frac{5.75}{3.5}$

$\left(\frac{1.25}{1.16}\right)^t>1.64285714286$

$t\cdot\ln\left(\frac{1.25}{1.16}\right)>\ln\left(1.64285714286\right)$

$t>\frac{\ln\left(1.64285714286\right)}{\ln\left(\frac{1.25}{1.16}\right)}$

$t>6.6436473051$

Hence final answer is approx 6.644 years.