Last year, Joe had to invest. He invested some of it in an account that paid simple interest per year, and he invested the rest in an account that paid simple interest per year. After one year, he received a total of in interest. How much did he invest in each account?
x = amount in the first account
y = amount in the second account.
total invested:
x + y = 10,000
since Interest = Principles times rate times time.
.07x + .08y = 860
Now, you work with those two equations.
I would multiply the bottom equation by 100 to get rid of the decimals.
x + y = 10000
7x + 8y = 86000
Now, you can solve this by using the substitution method or the addition method.
I probably would use the addition(also known as the elimination method.)
Multiply the top equation by -7 and solve for y. Once you have y, you can find x. Then be sure to check x and y in both equations.
Do you have numbers for this problem?
Last year, Joe had 10,000 to invest. He invested some of it in an account that paid 7% simple interest per year, and he invested the rest in an account that paid 9% simple interest per year. After one year, he received a total of $860 in interest. How much did he invest in each account?
(sorry bout that).
where did you get .08 from?
Sorry.. the .08 is a typo. It should be .09
Which makes the equation 7x + 9y = 86000
it would be 7x+7y=70000? I don't know how to solve the two equations
I don't think I'm doing this right because i am getting HUGE numbers like 156,000
-7x -7y =70000
7x + 9y =86000
2y = 156000
divide by 2 and you get 7800 for y
so the other amount must be 2200.
To solve this problem, we need to set up a system of equations. Let's denote the amount Joe invested in the first account as 'x' and the amount he invested in the second account as 'y'.
Since we know he invested all of his money, we can express their relationship as:
x + y =
Now let's consider the interest earned from each account. The first account pays simple interest of 'r1' per year, so the interest earned from the first account will be:
(x * r1)
Similarly, the second account pays simple interest of 'r2' per year, so the interest earned from the second account will be:
(y * r2)
According to the problem, the total interest earned after one year is . Therefore, we can set up another equation:
(x * r1) + (y * r2) =
In summary, we have the following system of equations:
1) x + y =
2) (x * r1) + (y * r2) =
To solve this system, we need to know the values of , r1, r2, and in order to find the values of x and y that satisfy the equations. Without these values, we cannot determine the exact amount Joe invested in each account.