Two investments are made summing up to 8,800. For a certain year, theseinvestments yield P1,326 in simple interest. Part of the investment is allotted for14% and part for 16%. Find the amount invested at each rate

Respuesta :

Given:

a.) Two investments are made summing up to 8,800.

b.) For a certain year, these investments yield P1,326 in simple interest.

c.) Part of the investment is allotted for 14% and part for 16%.

Recall: The simple interest formula.

[tex]\text{ I = Prt}[/tex]

Where,

I = interest

P = principal amount

r = interest rate

t = time (in year)

Step 1:

P = 8,800

But it's been made into two investments.

Let,

A = investment 1

B = investment 2

We get,

A + B = 8,800 = P (Equation 1)

Step 2:

Part of the investment is allotted for 14% and part for 16%.

Thus,

For investment 1:

Ia = Art = A(14/100)(1) = 0.14A

For investment 2:

Ib = Brt = B(16/100)(1) = 0.16B

We get,

0.14A + 0.16B = 1,326 (Equation 2)

Step 3:

Substitute Equation 1 to Equation 2.

A + B = 8,800

A = 8,800 - B

0.14A + 0.16B = 1,326

0.14(8,800 - B) + 0.16B = 1,326

1,232 - 0.14B + 0.16B = 1,326

0.02B = 1,326 - 1,232

0.02B = 94

0.02B/0.02 = 94/0.02

B = 4,700

Let's now find A.

A + B = 8,800

A + 4,700 = 8,800

A = 8,800 - 4,700

A = 4,100

In Summary:

The amount invested at 14% is 4,100

The amount invested at 16% is 4,700