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2 years ago

For brainliest Rob is saving up to buy an mp3 player

Mathematics

1 answer:

nikklg [1K]2 years ago

4 0

Step-by-step explanation:

for 15 =6

75=?(x)

15x=75×6

15x=450

x=450/15

x=30

Rob saved $30

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The monthly fees for single rooms at five colleges are $370, $310,$380,$340, and $310, respectively what is the mean of these mo

noname [10]

Answer:

$342

Step-by-step explanation:

370+310+380+340+310=1710

1710/5=342

8 0

3 years ago

Read 2 more answers

A box with a hinged lid is to be made out of a rectangular piece of cardboard that measures 3 centimeters by 5 centimeters. Six

kherson [118]

Answer:

x = 0.53 cm

Maximum volume = 1.75 cm³

Step-by-step explanation:

Refer to the attached diagram:

The volume of the box is given by

$V = Length \times Width \times Height \\\\$

Let x denote the length of the sides of the square as shown in the diagram.

The width of the shaded region is given by

$Width = 3 - 2x \\\\$

The length of the shaded region is given by

$Length = \frac{1}{2} (5 - 3x) \\\\$

So, the volume of the box becomes,

$V = \frac{1}{2} (5 - 3x) \times (3 - 2x) \times x \\\\V = \frac{1}{2} (5 - 3x) \times (3x - 2x^2) \\\\V = \frac{1}{2} (15x -10x^2 -9 x^2 + 6 x^3) \\\\V = \frac{1}{2} (6x^3 -19x^2 + 15x) \\\\$

In order to maximize the volume enclosed by the box, take the derivative of volume and set it to zero.

$\frac{dV}{dx} = 0 \\\\\frac{dV}{dx} = \frac{d}{dx} ( \frac{1}{2} (6x^3 -19x^2 + 15x)) \\\\\frac{dV}{dx} = \frac{1}{2} (18x^2 -38x + 15) \\\\\frac{dV}{dx} = \frac{1}{2} (18x^2 -38x + 15) \\\\0 = \frac{1}{2} (18x^2 -38x + 15) \\\\18x^2 -38x + 15 = 0 \\\\$

We are left with a quadratic equation.

We may solve the quadratic equation using quadratic formula.

The quadratic formula is given by

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

Where

$a = 18 \\\\b = -38 \\\\c = 15 \\\\$

$x=\frac{-(-38)\pm\sqrt{(-38)^2-4(18)(15)}}{2(18)} \\\\x=\frac{38\pm\sqrt{(1444- 1080}}{36} \\\\x=\frac{38\pm\sqrt{(364}}{36} \\\\x=\frac{38\pm 19.078}{36} \\\\x=\frac{38 + 19.078}{36} \: or \: x=\frac{38 - 19.078}{36}\\\\x= 1.59 \: or \: x = 0.53 \\\\$

Volume of the box at x= 1.59:

$V = \frac{1}{2} (5 – 3(1.59)) \times (3 - 2(1.59)) \times (1.59) \\\\V = -0.03 \: cm^3 \\\\$

Volume of the box at x= 0.53:

$V = \frac{1}{2} (5 – 3(0.53)) \times (3 - 2(0.53)) \times (0.53) \\\\V = 1.75 \: cm^3$

The volume of the box is maximized when x = 0.53 cm

Therefore,

x = 0.53 cm

Maximum volume = 1.75 cm³

7 0

3 years ago

13 is 6 1/2% of what number?

mylen [45]

Answer:

200

Step-by-step explanation:

3 0

1 year ago

400 UCF students were randomly selected and asked if they preferred washing their hands with soap and water or using hand saniti

kirill [66]

Answer:

1. a. z test for means and t test for means.

2. C. HA : mu1 - mu2 > 0

Step-by-step explanation:

Hypothesis testing is used in a situation where there are more than 1 alternative available. The t test is conducted in the mean which determines the t value and then this value is compared with p value to identify the situation whether to accept or reject the null hypothesis. The alternative hypothesis in this situation is is represented by mu.

6 0

2 years ago

Can someone help me out please!?

Nezavi [6.7K]

48 on call = 3.5 hours for 10 dollars = 1/2 hours for 1.5

6 0

3 years ago