Question 150607
Let the amount invested at 18% = {{{x}}}
Then the amount invested at 12% = {{{3x}}}
{{{.18x + .12*3x = 2200}}}
{{{.18x + .36x = 2200}}}
{{{.54x = 2200}}}
{{{x = 4074}}}
{{{3x = 12222}}}
4074 pesos were invested @ 18% and 12,222 pesos were 
invested @ 12%