Question

How much is invested At %6 and at % 10

Answer 1

Let x be the amount invested in the 6% account and y be the amount invested in the 10%. then we can set the following system of equations:

`\begin{gathered} 0.06x+0.10y=470, \\ x+y=7000. \end{gathered}`

Substracting y from the second equation we get:

`x=7000-y\text{.}`

Substituting the above equation in the first one we get:

`0.06(7000-y)+0.10y=470.`

Simplifying the above result we get:

`\begin{gathered} 420-0.06y+0.10y=470, \\ 420+0.04y=470. \end{gathered}`

Subtracting 420 from the above equation we get:

`\begin{gathered} 420+0.04y-420=470-420, \\ 0.04y=50. \end{gathered}`

Dividing the above equation by 0.04 we get:

`\begin{gathered} (0.04y)/(0.04)=(50)/(0.04), \\ y=1250. \end{gathered}`

Finally, substituting y=1250 at x=7000-y we get:

`\begin{gathered} x=7000-1250, \\ =5750. \end{gathered}`

Answer:

$5750 at 6%.

$1250 at 10%.