Question

The number of music CDs sold in 2003 by one company was approximately 1.5 x 10^5. The number of music CDs sold by thesame company in 2013 was approximately 7.1 x 10^7. What is the difference in CDs sold between 2003 and 2013?

Answer 1

Given:

`\begin{gathered} \text{Number of music CDs sold in 2003 = 1.5 }*10^5 \\ \text{Number of music CDs sold in 2013 = 7.1 }*10^7 \end{gathered}`

Solution

The difference between the number of CDs sold between 2003 and 2103:

`\text{Difference = Number of CDs in 2013 - Number of CDs in 2003}`

Substituting, we have:

`\begin{gathered} \text{Difference = 7.1 }*10^7\text{ - 1.5 }*10^5 \\ =\text{ 7.1 }*10^2\text{ }*10^5\text{ - 1.5 }*10^5 \\ =10^5(710-1.5) \\ =\text{ 708.5 }*10^5 \\ =\text{ 7.085 }*10^7 \end{gathered}`

Answer: 7.085 x 10^7