Translating verbal descriptions into algebraic expressions

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I'm trying to solve the following problem but the result I'm getting is not logical given the data of the problem.

Pat invested a total of \$30,000. Part of the money was invested in a money marketing account that paid 10 percent simple annual interest, and the remainder of the money was invested in a fund that paid 8 percent simple annual interest. If the interest earned at the end of the first year from these investments was \$256, how much did Pat invest at 10 percent and how much at 8 percent?

I got the following two formulas from the problem:

$$x + y = 3000$$

$$x\left (1 + \frac{10\left (1 \right )}{100} \right ) + y\left (1 + \frac{8\left (1 \right )}{100} \right ) = 256$$

To calculate the simple interest I'm using the following formula:

$$V=P\left ( 1 + \frac{rt}{100} \right )$$

where:

  • $V$ = Investment

  • $t$ = years

  • $P$ = amount of money invested

  • $r$ = simple annual interest rate

Using the elimination method, $y$ has a value of $152,200$, which is not logical.

Can someone tell me what I'm doing wrong?

Best regards,

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The interest earned on $x$ is $10\%$ of $x$, not $110\%$ of $x$. Similar for the $y$ term.