A woman invests $15000 in 2 separate investment accounts.
One account earns 5.1%, one earns 4.2% simple interest.
If she earns $21 in interest total, how much did she earn from each account.
I keep getting x to be 67,666.67 by getting to this equation:
.051x + .042(15000-x) = 21
Very confused.
That's because there's a mistake in the problem.
Even if it were all invested at 4.2%, she'd earn .042*15000 = $630 in interest.
That $21 interest is bogus. It must be $2100 or something.
To solve the problem, you first need to write two equations representing the total interest earned from each account.
Let's assume that she invested "x" dollars in the account earning 5.1% interest, and therefore, she invested (15000 - x) dollars in the account earning 4.2% interest.
The first equation represents the interest earned from the account with 5.1% interest:
Interest1 = (Principal1) * (Rate1) = x * 0.051
The second equation represents the interest earned from the account with 4.2% interest:
Interest2 = (Principal2) * (Rate2) = (15000 - x) * 0.042
Since we know the total interest earned is $21, we can write the equation:
Interest1 + Interest2 = 21
Now we can substitute the equations for Interest1 and Interest2 into the equation for the total interest earned:
x * 0.051 + (15000 - x) * 0.042 = 21
Simplifying the equation:
0.051x + 0.042(15000 - x) = 21
0.051x + 630 - 0.042x = 21
0.009x + 630 = 21
0.009x = 21 - 630
0.009x = -609
x = -609 / 0.009
x ≈ -67777.78
It seems there might be an error in your calculations or the given information. Please double-check the values and make sure there are no typos.