Phyllis invested 50000 dollars, a portion earning a simple interest rate of 5 percent per year and the rest earning a rate of 7 percent per year. After one year the total interest earned on these investments was 2720 dollars. How much money did she invest at each rate?

The amount invested at 5% was $39,000 and the amount invested at 7% was $11,000

Step-by-step explanation:

we know that

The simple interest formula is equal to

where

I is the Final Interest Value

P is the Principal amount of money to be invested

r is the rate of interest  

t is Number of Time Periods

Let

x-----> the amount invested at 5%

50,000-x -----> the amount invested at 7%

so

substitute in the formula above

solve for x

therefore

The amount invested at 5% was $39,000 and the amount invested at 7% was $11,000