Please help me with this question:

An actor invests some money at 7%, and $24000 more than four times the amount at 8%. The total annual interest earned from the i

natita [175]

Answer:

$70,000 at 7%
$304,000 at 8%

Step-by-step explanation:

Given:

Total interest earned on two investments is $29,220.

An amount is invested at 7%.

$24,000 more than 4 times that amount is invested at 8%.

Find:

The amount invested at each rate.

Solution:

Our strategy will be to define a variable representing the amount invested at 7%, use that variable to write an expression for the amount invested at 8%, then write an equation for the total return on the investments.

Let x represent the amount invested at 7%. Then (24,000+4x) will be the amount invested at 8%. The total interest earned will be ...

interest on 7% account + interest on 8% account = total interest

0.07x + 0.08(24000+4x) = 29220

0.39x + 1920 = 29220 . . . . . . . . . . . simplify

0.39x = 27300 . . . . . . . . . . . . . . . . . .subtract 1920

x = 27300/0.39 = 70000 . . . . . . . . . divide by the coefficient of x

24,000 +4x = 24,000 +280,000 = 304,000 . . . . amount invested at 8%

He invested $70,000 at 7% and $304,000 at 8%.

Check

The answer must satisfy ...

7% interest + 8% interest = 29,220

0.07×70,000 +0.08×304,000 = 4,900 +24,320 = 29,220 . . . . as required

_____

Comment on 6-step method

We have tried to hit the highlights. Your steps appear to be ...

Identify the given information (Given)
Identify the question you are asked to answer (Find)
Identify the useless information in the problem statement (is none)
Decide on a strategy. Make a model or drawing. (model equation shown)
Solve and show work (Solution)
Explain why the answer makes sense (Check)

6 0

3 years ago

once a week you babysit your neighbor’s toddler after school, usually going to a local playground. you notice that each swing on

Natalka [10]

You didn't include the formula.

Given that there is no data about the mass, I will suppose that the formula is that of the simple pendulum (which is only valid if the mass is negligible).

Any way my idea is to teach you how to use the formula and you can apply the procedure to the real formula that the problem incorporates.

Simple pendulum formula:

Period = 2π √(L/g)

Square both sides

Period^2 = (2π)^2 L/g

L = [Period / 2π)^2 * g

Period = 3.1 s
2π ≈ 6.28
g ≈ 10 m/s^2

L = [3.1s/6.28]^2 * 10m/s^2 =2.43 m

I hope this helps you.

6 0

3 years ago

Which of the following is an example of increasing both current liability and use assets?

kow [346]

I think you forgot to give the options along with the question. i am answering the question based on my knowledge and research. "Trading in an old car for a newer car and financing the balance" is an example of increasing both current liability and use assets. I hope that the answer has come to your help.

7 0

3 years ago

Read 2 more answers

Use the method of undetermined coefficients to find the general solution to the de y′′−3y′ 2y=ex e2x e−x

djverab [1.8K]

I'll assume the ODE is

$y'' - 3y' + 2y = e^x + e^{2x} + e^{-x}$

Solve the homogeneous ODE,

$y'' - 3y' + 2y = 0$

The characteristic equation

$r^2 - 3r + 2 = (r - 1) (r - 2) = 0$

has roots at $r=1$ and $r=2$ . Then the characteristic solution is

$y = C_1 e^x + C_2 e^{2x}$

For nonhomogeneous ODE (1),

$y'' - 3y' + 2y = e^x$

consider the ansatz particular solution

$y = axe^x \implies y' = a(x+1) e^x \implies y'' = a(x+2) e^x$

Substituting this into (1) gives

$a(x+2) e^x - 3 a (x+1) e^x + 2ax e^x = e^x \implies a = -1$

For the nonhomogeneous ODE (2),

$y'' - 3y' + 2y = e^{2x}$

take the ansatz

$y = bxe^{2x} \implies y' = b(2x+1) e^{2x} \implies y'' = b(4x+4) e^{2x}$

Substitute (2) into the ODE to get

$b(4x+4) e^{2x} - 3b(2x+1)e^{2x} + 2bxe^{2x} = e^{2x} \implies b=1$

Lastly, for the nonhomogeneous ODE (3)

$y'' - 3y' + 2y = e^{-x}$

take the ansatz

$y = ce^{-x} \implies y' = -ce^{-x} \implies y'' = ce^{-x}$

and solve for $c$ .

$ce^{-x} + 3ce^{-x} + 2ce^{-x} = e^{-x} \implies c = \dfrac16$

Then the general solution to the ODE is

$\boxed{y = C_1 e^x + C_2 e^{2x} - xe^x + xe^{2x} + \dfrac16 e^{-x}}$

6 0

1 year ago

Which inequality represents the sentence? The difference of seven and two tenths and a number is more than twenty nine. 7. 2 - n

Slav-nsk [51]

The inequality which represent, the difference of seven and two tenths and a number is more than twenty-nine, is

$7.2-n > 29$

<h3>What is the inequality equation?</h3>

Inequality equation is the equation in which the two expressions are compared with greater than, less than or other inequality signs.

Inequality is represented with the greater then(<), less then(>) or with the other inequity signs like less than equal to $\leq$ or greater than equal to $\geq$ .

Tenth is written as the fractional part of the number 10. The value of one tenth is equal to 1/10 or 0.1.

The sentence given for the inequality expression is, that the differences of seven and two tenths, and a number is more than twenty-nine.

The number seven and two tenths can be written as,

$7\dfrac{2}{10}$

Suppose the unknown number is n. Now, the differences of seven and two tenths, and this number (n) is more than twenty-nine. The more than word means, the greater than sign for equation. Thus, it can be expressed as,

$7\dfrac{2}{10}-n > 29\\\dfrac{72}{10}-n > 29\\7.2-n > 29$

Hence, the inequality which represent, the difference of seven and two tenths and a number is more than twenty-nine, is

$7.2-n > 29$

Learn more about the inequality equation here:

brainly.com/question/17724536

7 0

3 years ago