# If I invested $1,000,000 some of it at 3.5% and some at 4.5% and the interest return was $39,000. How much did I invest at each rate? (answer)

While the ways my colleagues have explained the question are the correct way to answer this question algebraically, it is often difficult to remember all the steps. I prefer to teach the guess and check as a back up method as it is much more relevant to real life situations. Example: Using...