Carcass wrote:
The number 980,000,000 is equal to \(9.8 × 10^n\), for some integer n. What is the value of n?
Key property: If we multiply \(k\) by \(10^n\), where \(n\) is a positive integer, then we take the decimal point in \(k\) and move it \(n\) spaces to the right.
For example, ...
\(9.8 × 10^1 = 98\) [the decimal point is moved 1 space to the right]
\(9.8 × 10^2 = 980\) [the decimal point is moved 2 spaces to the right]
\(9.8 × 10^3 = 9800\) [the decimal point is moved 3 spaces to the right]
And so on. To get \(980,000,000\), we must take the decimal point in \(9.8\) and move it \(8\) spaces to the right.
In other words, \(9.8 × 10^8 = 980,000,000\)