To answer this question, first, we will compute the intensity of each earthquake.
Recall that:
[tex]a=\log b\text{ if and only if }10^a=b.[/tex]
Therefore, using the given formula we get:
[tex]I=10^R.[/tex]
Then, the intensity of an earthquake that measures 7.5 on the Richter scale is:
[tex]I_{7.5}=10^{7.5},[/tex]
and the intensity of an earthquake which measures 2.3 on the Richter scale is:
[tex]I_{2.3}=10^{2.3}.[/tex]
Now, notice that:
[tex]\frac{I_{7.5}}{I_{2.3}}=\frac{10^{7.5}}{10^{2.3}}=10^{5.2}.[/tex]
We know that:
[tex]10^{5.2}\approx158489.32.[/tex]
Answer:
[tex]158489.32\text{ times more intense.}[/tex]