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3 years ago

HELP FAST!!!!! 26 pts

Mathematics

1 answer:

Yakvenalex [24]3 years ago

8 0

Answer is D) $300

Step-by-step explanation:

First find the rate of how many dollars she earns in 1 hour = $180/18

Mabel earns $10/h so 30 hours x $10 = $300/30 hours

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Sue is a software engineer. She wants to create a large scale drawing of a processor inside a cell phone. The processor is a squ

Alisiya [41]

Answer:

It is a 18 by 18 square

Step-by-step explanation:

8 0

3 years ago

8 increased by three times a number

nexus9112 [7]

The answer would be 24

6 0

3 years ago

A soup can in the shape of a right circular cylinder is to be made from two materials. The material for the side of the can cost

Advocard [28]

Answer:

Radius = 1.12 inches and Height = 4.06 inches

Step-by-step explanation:

A soup can is in the shape of a right circular cylinder.

Let the radius of the can is 'r' and height of the can is 'h'.

It has been given that the can is made up of two materials.

Material used for side of the can costs $0.015 and material used for the lids costs $0.027.

Surface area of the can is represented by

S = 2πr² + 2πrh ( surface area of the lids + surface are of the curved surface)

Now the function that represents the cost to construct the can will be

C = 2πr²(0.027) + 2πrh(0.015)

C = 0.054πr² + 0.03πrh ---------(1)

Volume of the can = Volume of a cylinder = πr²h

16 = πr²h

$h=\frac{16}{\pi r^{2}}$ -------(2)

Now we place the value of h in the equation (1) from equation (2)

$C=0.054\pi r^{2}+0.03\pi r(\frac{16}{\pi r^{2}})$

$C=0.054\pi r^{2}+0.03(\frac{16}{r})$

$C=0.054\pi r^{2}+(\frac{0.48}{r})$

Now we will take the derivative of the cost C with respect to r to get the value of r to get the value to construct the can.

$C'=0.108\pi r-(\frac{0.48}{r^{2} })$

Now for C' = 0

$0.108\pi r-(\frac{0.48}{r^{2} })=0$

$0.108\pi r=(\frac{0.48}{r^{2} })$

$r^{3}=\frac{0.48}{0.108\pi }$

r³ = 1.415

r = 1.12 inch

and h = $\frac{16}{\pi (1.12)^{2}}$

h = 4.06 inches

Let's check the whether the cost is minimum or maximum.

We take the second derivative of the function.

$C"=0.108+\frac{0.48}{r^{3}}$ which is positive which represents that for r = 1.12 inch cost to construct the can will be minimum.

Therefore, to minimize the cost of the can dimensions of the can should be

Radius = 1.12 inches and Height = 4.06 inches

5 0

3 years ago

Why is the mechanical advantage of using a single pulley always 1? Assume there’s no friction. A. The input force is in a differ

Luba_88 [7]

Answer:

D. The input force is equal to the output force

Step-by-step explanation:

A pulley changes the direction of the applied force, but does not change its magnitude. The mechanical advantage is the ratio of output force to input force, so must be 1 when the force magnitude does not change.

8 0

3 years ago

Which expression is equivalent?

gregori [183]

The correct option is: Option (C) $log_3c - log_{3}9$

Explanation:
It is the property of log that if it contains the fraction, it can be expressed as the difference of the log of numerator and the log of denominator.

The general form is:
$log( \frac{x}{y} ) = log(x) - log(y)$

Hence the correct answer is $log_3c - log_{3}9$ .

8 0

3 years ago