Question

Evaluate (3.0 x 10^-5)(2.0 x 10^9)

Answer 1

We are to evaluate

`(3.0x10^{-5\text{ }})(2.0x10^9)`

Removing the brackets, we have

`3.0x2.0x10^{-5\text{ }}x10^9`

=

`=6x10^{-5\text{ }}x10^9`

Applying the laws of indices

`10^{a\text{ }}x10^b=10^(a+b)`
`\begin{gathered} =6x10^{-5\text{ }}x10^9=6x10^(-5+9) \\ =6x10^4 \end{gathered}`

The answer is 6 x 10^4 or 60000