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Question 1206042:  An actor invests some money at 8%, and $22000 more than twice the amount at 12 %. The total annual interest earned from the investment is $30800. How much did he invest at each amount? 
 
 Answer by math_tutor2020(3817)      (Show Source): 
You can  put this solution on YOUR website!  
x = some amount of money invested at 8% interest rate 
2x+22000 = amount invested at 12%
 
 
A = 0.08x = amount of interest earned from the 8% account 
B = 0.12*(2x+22000) = interest earned from the 12% account 
Each duration is for 1 year.  
I'll assume simple interest is used, and not compound interest.
 
 
A+B = total interest earned for 1 year 
A+B = 0.08x+0.12*(2x+22000) = 30800
 
 
Let's isolate x. 
0.08x+0.12*(2x+22000) = 30800 
0.08x+0.12*(2x)+0.12*(22000) = 30800 
0.08x+0.24x+2640 = 30800 
0.32x+2640 = 30800 
0.32x = 30800-2640  
0.32x = 28160  
x = 28160/0.32  
x = $88,000 was invested at 8%
 
 
And, 
2x+22000 = 2*88000+22000 = $198,000 was invested at 12%
 
 
Check: 
0.08*88000 + 0.12*198000 = 30800 
The answers are confirmed. 
  
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