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Ean had money in two savings accounts one rate is 7% akd the other is 8% if he has 450 more in the 8% account and the total interest is 249 how muchbis invested in each savings account

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Answer:

$1420 was invested in the 7% account.

$1870 was invested in the 8% account.

Explanation:

  • We will need a system of equations to find the amounts invested in each account.
  • We can allow x to represent the amount invested in the 7% account and y to represent the amount invested in the 8% account.
  • For our system, we need to use the decimal forms of the interest rates (i.e., 0.07 and 0.08)

First equation:

We know that the sum of the interests from both accounts equals the total interest:

(7% interest rate * investment) + (8% interest rate * investment) = total interest

Since the total interest is $249, our first equation is given by:

0.07x + 0.08y = 249

Second equation:

Since Ean has 450 more in the 8% account, our second equation is given by:

y = x + 450

Method to solve: Substitution:

We can first find x (i.e., the amount invested in the 7% account) by substituting x + 450 for y in the first equation (i.e., 0.07x + 0.08y = 249):

Finding x, the amount invested in the 7% account:

0.07x + 0.08(x + 450) = 249

0.07x + 0.08x + 36 = 249

(0.15x + 36 = 249) - 36

(0.15x = 213) / 0.15

x = 1420

Thus, $1420 was invested in the 7% account.

Finding y, the amount invested in the 8% account:

Now we can find y (i.e., the amount invested in the 8% account) by plugging in 1420 for x in the second equation (i.e., y = x + 450):

y = 1420 + 450

y = 1870

Thus, $1870 was invested in the 8% account.

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