159k views
3 votes
You invest a total of $12,000 in two savings accounts paying 0.61% and 0.70% simple annual interest. If the yearly interest is $75, how much of the $12,000 did you deposit into each account?

1.Focus on the question at the end of the situation. What is unknown? Define variables to represent these unknowns.

2. What are the TWO situations that are being described in the problem? Write an equation that represents each situation.

User Shonique
by
8.0k points

1 Answer

5 votes

Answer:

Explanation:

To represent the unknowns, let x be the amount of money deposited into the first account paying 0.61% simple annual interest and y be the amount of money deposited into the second account paying 0.70% simple annual interest.

The first situation is that the total deposit into the first account is x and the interest earned on that account is (0.61/100)x. The second situation is that the total deposit into the second account is y and the interest earned on that account is (0.70/100)y.

The equation representing the first situation is: (0.61/100)x = (75/12000)x

The equation representing the second situation is: (0.70/100)y = (75/12000)y

The sum of the deposit in both accounts must be equal to $12,000, so we can write the third equation: x + y = 12,000

The system of equations is:

(0.61/100)x = (75/12000)x

(0.70/100)y = (75/12000)y

x + y = 12,000

You can use systems of equation methods like substitution, elimination or graphing to find the solution.

To find the solution, we can use the substitution method. We can start by isolating x or y in one of the equations, then substitute it into the other equation.

Let's start with the equation x + y = 12,000. We'll solve for x:

x = 12,000 - y

Now we can substitute this value of x into the first equation:

(0.61/100)(12,000 - y) = (75/12000)(12,000 - y)

Solving for y, we get:

y = $7,200

Now we can substitute this value of y back into the equation x + y = 12,000 to find x:

x = 12,000 - y = 12,000 - $7,200 = $4,800

So the solution is:

x = $4,800 and y = $7,200

This means you deposited $4,800 in the first account and $7,200 in the second account.

User Ivo
by
7.4k points