Answer:
Phyllis invested $11,000 at a simple interest rate of 7 percent per year and $40,000 at a simple interest rate of 4 percent per year.
Step-by-step explanation:
From the information provided, you can write the following equations:
x+y=51000 (1)
0.04x+0.07y=2370 (2), where
x is the portion earning a simple interest rate of 4 percent per year
y is the portion earning a simple interest rate of 7 percent per year
First, you can isolate x in (1):
x=51000-y (3)
Now, you can replace (3) in (2) and solve for y:
0.04(51000-y)+0.07y=2370
2040-0.04y+0.07y=2370
0.03y=330
y=330/0.03
y=11000
Then, you can replace the value of y in (3) to find the value of x:
x=51000-11000
x=40000
According to this, the answer is that Phyllis invested $11,000 at a simple interest rate of 7 percent per year and $40,000 at a simple interest rate of 4 percent per year.
