Question

Cassandra invested one part of her $10,000at7.5$820. How much did she invest at each rate?

Answer 1

Let $x$ and $y$x be the amount invested at $7.5\%$ and $8.5\%$ respectively

Income =820 = 7.5\times x + 8.5\times y$

The total amount invested is also known

$10,000=x+y$

Solve the system of the equations to find $x$ and $y.$

$x=$3000\ and\ y = $7000$

As a practice check that $7.5\%$ of 3000$and$8.5\%$of$ $7000$ gives 820$