How many times larger ? Is 1.815x10^3 and 4.975x10^12??????

For this case we have the following data:
Debt in September 2015:[tex]1.815 * 10^{13}[/tex]
Debt in September 2005:[tex]4.975 * 10^{12}[/tex]
The debt in September 2015 can be rewritten as follows:
[tex]18.15 * 10^{12}[/tex]
In this way, we divide the 2015 debt between the 2005 debt, obtaining:
[tex]\frac{ 18.15 * 10^{12}}{ 4.975 * 10^{12} }=3.65[/tex]
Thus, the 2015 debt is 3.65 times larger than the 2005 debt.
Answer:
3.65 times larger