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Larry Mitchell invested part of his $39,000 advance at 2% annual simple interest and the rest at 4% annual simple interest. If his total yearly interest from both accounts was $820, find the amount invested at each rate.

a.The amount invested at 2% is $____
b.The amount invested at 4% is $____.

User Andreu
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Final answer:

Larry Mitchell invested $2000 at 2% annual simple interest and $37000 at 4% annual simple interest.

Step-by-step explanation:

Let's assume that Larry Mitchell invested $x at 2% annual simple interest and $y at 4% annual simple interest, with a total yearly interest of $820. To solve this problem, we can set up a system of equations:

x + y = 39000 (equation 1)

0.02x + 0.04y = 820 (equation 2)

We can now solve this system of equations using substitution or elimination. Let's use elimination method:

Multiplying equation 1 by 0.02, we get: 0.02x + 0.02y = 780 (equation 3)

Subtracting equation 3 from equation 2, we get: 0.02y - 0.02y = 820 -780

0.02x = 40

x = 40/0.02

x = $2000

Substituting the value of x into equation 1, we get: $2000 + y = 39000

y = 39000 - 2000

y = $37000

The amount invested at 2% is $2000 and the amount invested at 4% is $37000.

User Nasser Tahani
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