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3 years ago

13

What is the amount of interest I earned on $4000 deposited in a savings account with 4% interest compounded annually after 4 yea

rs?

1 answer:

Dominik [7]3 years ago

6 0

Answer:

640 would be your interest.

Step-by-step explanation:

I'm not sure if htis is correct.. but to get interest u multiply rate part and time.

You might be interested in

A flagpole casts a shadow that is 85 feet long. Paul is 6 feet tall, and while standing next to the flagpole, casts a shadow tha

hammer [34]

Answer:

51m

Step-by-step explanation:

-Paul is 6ft, and has a 10ft shadow. The pole has a 85ft shadow:

-Using ratios:

$\frac{Height\ of \ object}{Height\ of \ shadow}$

Let h be the height of the flagpole:

$=>\frac{6}{10}=\frac{h}{85}\\\\h=\frac{6\times 85}{10}\\\\h=51$

Hence, the height of the pole is 51m

6 0

3 years ago

A metal cylinder can with an open top and closed bottom is to have volume 4 cubic feet. Approximate the dimensions that require

Aleksandr-060686 [28]

Answer:

$r\approx 1.084\ feet$

$h\approx 1.084\ feet$

$\displaystyle A=11.07\ ft^2$

Step-by-step explanation:

<u>Optimizing With Derivatives </u>

The procedure to optimize a function (find its maximum or minimum) consists in :

Produce a function which depends on only one variable
Compute the first derivative and set it equal to 0
Find the values for the variable, called critical points
Compute the second derivative
Evaluate the second derivative in the critical points. If it results positive, the critical point is a minimum, if it's negative, the critical point is a maximum

We know a cylinder has a volume of 4 $ft^3$ . The volume of a cylinder is given by

$\displaystyle V=\pi r^2h$

Equating it to 4

$\displaystyle \pi r^2h=4$

Let's solve for h

$\displaystyle h=\frac{4}{\pi r^2}$

A cylinder with an open-top has only one circle as the shape of the lid and has a lateral area computed as a rectangle of height h and base equal to the length of a circle. Thus, the total area of the material to make the cylinder is

$\displaystyle A=\pi r^2+2\pi rh$

Replacing the formula of h

$\displaystyle A=\pi r^2+2\pi r \left (\frac{4}{\pi r^2}\right )$

Simplifying

$\displaystyle A=\pi r^2+\frac{8}{r}$

We have the function of the area in terms of one variable. Now we compute the first derivative and equal it to zero

$\displaystyle A'=2\pi r-\frac{8}{r^2}=0$

Rearranging

$\displaystyle 2\pi r=\frac{8}{r^2}$

Solving for r

$\displaystyle r^3=\frac{4}{\pi }$

$\displaystyle r=\sqrt[3]{\frac{4}{\pi }}\approx 1.084\ feet$

Computing h

$\displaystyle h=\frac{4}{\pi \ r^2}\approx 1.084\ feet$

We can see the height and the radius are of the same size. We check if the critical point is a maximum or a minimum by computing the second derivative

$\displaystyle A''=2\pi+\frac{16}{r^3}$

We can see it will be always positive regardless of the value of r (assumed positive too), so the critical point is a minimum.

The minimum area is

$\displaystyle A=\pi(1.084)^2+\frac{8}{1.084}$

$\boxed{ A=11.07\ ft^2}$

8 0

3 years ago

A vitamin C tablet contains 1/40 of a gram of vitamin C. You take 1 1/2 tablets every day. How many grams of vitamin C do you ta

enyata [817]

1/40*1.5=3/80=0.0375

8 0

3 years ago

Help me please TY WHOEVER HELPS

Natali [406]

Answer:

picture too bad sorry

Step-by-step explanation:

8 0

3 years ago

What is the length of segment AB?<br> Consider the diagram.<br> 7,9,18,25

Mrrafil [7]

Answer:

9

Step-by-step explanation:

It is congruent to the other side.

5 0

3 years ago