Question 1103963
let x = the amount of money she invested at 8%.
then 2 * x = the amount of money she invested at 5%.


.08 * x + .05 * 2 * x = 4200.


simplify to get .08 * x + .10 * x = 4200.


combine like terms to get .18 * x = 4200.


divide both sides of this equation by .18 to get x = 23,333.33 rounded to 2 decimal places.


2x is therefore equal to 46,666.67 rounded to 2 decimal places.


you get .08 * 23,333.33 + .05 * 46,666.67 = 4200.


i used the unrounded numbers to do the calculations.


your solution is that she invested 23,333.33 at 8% and 46,666.67 at 5%.