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3 years ago

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For his mobile phone service, John pays a monthly fee of $40 plus $15 for each 1 GB of data (rounded up) over his 8 GB of data t

hat comes with his plan. For his monthly charge before taxes to be at most $70, how many gigabytes of data can he use in a month

1 answer:

kolbaska11 [484]3 years ago

3 0

Answer:

John can use no more than 2 GB of additional data

Step-by-step explanation:

Monthly fee = $40

Additional fee = $15 for each 1 GB of data (rounded up) over his 8 GB.

Let x be the number of additional data in GB over his 8 GB of data that comes with his plan.

Total monthly charge is

$C(x)=40+15x$

It is given that monthly charge before taxes to be at most $70.

$C(x)\leq 70$

$40+15x\leq 70$

$15x\leq 70-40$

$15x\leq 30$

Divide both sides by 2.

$x\leq 2$

Therefore, John can use no more than 2 GB of additional data.

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In 2016, the mean number of wins for teams in Major League Baseball was 81 wins with a standard deviation of 10.7 wins. (a) The

Kay [80]

Answer:

(a) The Chicago Cubs broke the Curse of the Billy Goat by winning the World Series in 2016. Find and interpret the z-score for the Chicago Cubs, who had 103 wins in 2016.

Z score = 2.05607

Interpreting the z score, since the z score is positive, this means, the data point is to the right of the mean.

(b) The Chicago White Sox had a z-score of 20.28. Find the number of wins for the Chicago White Sox for 2016.

= 298 wins

Step-by-step explanation:

In 2016, the mean number of wins for teams in Major League Baseball was 81 wins with a standard deviation of 10.7 wins.

(a) The Chicago Cubs broke the Curse of the Billy Goat by winning the World Series in 2016. Find and interpret the z-score for the Chicago Cubs, who had 103 wins in 2016.

The formula for calculating a z-score is is z = (x-μ)/σ,

where x is the raw score

μ is the population mean

σ is the population standard deviation.

x = 103 wins, μ = 81 wins, σ = 10.7

z = 103 - 81/10.7

z = 2.05607

Interpreting the z score, since the z score is positive, this means, the data point is to the right of the mean.

(b) The Chicago White Sox had a z-score of 20.28. Find the number of wins for the Chicago White Sox for 2016.

The formula for calculating a z-score is is z = (x-μ)/σ,

where x is the raw score

μ is the population mean

σ is the population standard deviation.

From the above question, we are asked to find the number of wins, this means we should find the raw score = x

z = 20.28, x = ? μ = 81 , σ = 10.7

Hence,

20.28 = x - 81/10.7

Cross Multiply

20.28 × 10.7 = x - 81

216.996 = x - 81

x = 216.996 + 81

x = 297.996

x is approximately 298 wins

Therefore, the number of wins for the Chicago White Sox for 2016 is approximately 298 wins

4 0

3 years ago

Triangle X Y Z is shown. Angle Y X Z is a right angle. The length of Y X is 12 inches and the length of X Z is 10 inches. Angle

mario62 [17]

The best approximation for the measure of angle XYZ is 39.8° ⇒ 2nd answer

Step-by-step explanation:

Let us revise the trigonometry ratios in the right triangle ABC, where B is the right angle, AC is the hypotenuse, AB and BC are the legs of the triangle

The trigonometry ratios of the angle BAC, the opposite side to this angle is BC and the adjacent side to it is AB are

$sin(BAC)=\frac{opposite}{hypotenuse}=\frac{BC}{AC}$
$cos(BAC)=\frac{adjacent}{hypotenuse}=\frac{AB}{AC}$
$tan(BAC)=\frac{opposite}{adjacent}=\frac{BC}{AB}$

In Δ XYZ

∵ ∠ YXZ is a right angle

∴ The hypotenuse is YZ

∵ The adjacent side to ∠XYZ is XY

∵ The opposite side to ∠XYZ is XZ

∵ YX = 12 units

∵ XZ = 10 units

- Use tan ratio to find the measure of the angle because you

have the adjacent and opposite sides of the angle XYZ

∵ m∠XYZ is x

∵ $tan(x)=\frac{XZ}{XY}$

∴ $tan(x)=\frac{10}{12}$

- To find x use the inverse of tan(x)

∵ $x=tan^{-1}(\frac{10}{12})$

∴ x = 39.8°

∴ m∠XYZ = 39.81°

The best approximation for the measure of angle XYZ is 39.8°

Learn more:

You can learn more about the trigonometry ratios in brainly.com/question/4924817

#LearnwithBrainly

4 0

3 years ago

Read 2 more answers

What multiplication expression can you use to solve 2 divided by 8 4/5?

valina [46]

2*(5/44)

Dividing fractions means take the reciprocal of the second fraction then multiply
Find the reciprocal of 8 4/5
44/5 becomes 5/44
Then multiply by 2

8 0

3 years ago

Solve the following differential equation using using characteristic equation using Laplace Transform i. ii y" +y sin 2t, y(0) 2

kifflom [539]

Answer:

The solution of the differential equation is $y(t)= - \frac{1}{3} Sin(2t)+2 Cos(t)+\frac{5}{3} Sin(t)$

Step-by-step explanation:

The differential equation is given by: y" + y = Sin(2t)

<u>i) Using characteristic equation:</u>

The characteristic equation method assumes that y(t)= $e^{rt}$ , where "r" is a constant.

We find the solution of the homogeneus differential equation:

y" + y = 0

$y'=re^{rt}$

$y"=r^{2}e^{rt}$

$r^{2}e^{rt}+e^{rt}=0$

$(r^{2}+1)e^{rt}=0$

As $e^{rt}$ could never be zero, the term (r²+1) must be zero:

(r²+1)=0

r=±i

The solution of the homogeneus differential equation is:

$y(t)_{h}=c_{1}e^{it}+c_{2}e^{-it}$

Using Euler's formula:

$y(t)_{h}=c_{1}[Sin(t)+iCos(t)]+c_{2}[Sin(t)-iCos(t)]$

$y(t)_{h}=(c_{1}+c_{2})Sin(t)+(c_{1}-c_{2})iCos(t)$

$y(t)_{h}=C_{1}Sin(t)+C_{2}Cos(t)$

The particular solution of the differential equation is given by:

$y(t)_{p}=ASin(2t)+BCos(2t)$

$y'(t)_{p}=2ACos(2t)-2BSin(2t)$

$y''(t)_{p}=-4ASin(2t)-4BCos(2t)$

So we use these derivatives in the differential equation:

$-4ASin(2t)-4BCos(2t)+ASin(2t)+BCos(2t)=Sin(2t)$

$-3ASin(2t)-3BCos(2t)=Sin(2t)$

As there is not a term for Cos(2t), B is equal to 0.

So the value A=-1/3

The solution is the sum of the particular function and the homogeneous function:

$y(t)= - \frac{1}{3} Sin(2t) + C_{1} Sin(t) + C_{2} Cos(t)$

Using the initial conditions we can check that C1=5/3 and C2=2

<u>ii) Using Laplace Transform:</u>

To solve the differential equation we use the Laplace transformation in both members:

ℒ[y" + y]=ℒ[Sin(2t)]

ℒ[y"]+ℒ[y]=ℒ[Sin(2t)]

By using the Table of Laplace Transform we get:

ℒ[y"]=s²·ℒ[y]-s·y(0)-y'(0)=s²·Y(s) -2s-1

ℒ[y]=Y(s)

ℒ[Sin(2t)]= $\frac{2}{(s^{2}+4)}$

We replace the previous data in the equation:

s²·Y(s) -2s-1+Y(s) = $\frac{2}{(s^{2}+4)}$

(s²+1)·Y(s)-2s-1= $\frac{2}{(s^{2}+4)}$

(s²+1)·Y(s)= $\frac{2}{(s^{2}+4)}+2s+1=\frac{2+2s(s^{2}+4)+s^{2}+4}{(s^{2}+4)}$

Y(s)= $\frac{2+2s(s^{2}+4)+s^{2}+4}{(s^{2}+4)(s^{2}+1)}$

Y(s)= $\frac{2s^{3}+s^{2}+8s+6}{(s^{2}+4)(s^{2}+1)}$

Using partial franction method:

$\frac{2s^{3}+s^{2}+8s+6}{(s^{2}+4)(s^{2}+1)}=\frac{As+B}{s^{2}+4} +\frac{Cs+D}{s^{2}+1}$

2s^{3}+s^{2}+8s+6=(As+B)(s²+1)+(Cs+D)(s²+4)

2s^{3}+s^{2}+8s+6=s³(A+C)+s²(B+D)+s(A+4C)+(B+4D)

We solve the equation system:

A+C=2

B+D=1

A+4C=8

B+4D=6

The solutions are:

A=0 ; B= -2/3 ; C=2 ; D=5/3

So,

Y(s)= $\frac{-\frac{2}{3} }{s^{2}+4} +\frac{2s+\frac{5}{3} }{s^{2}+1}$

Y(s)= $-\frac{1}{3} \frac{2}{s^{2}+4} +2\frac{s }{s^{2}+1}+\frac{5}{3}\frac{1}{s^{2}+1}$

By using the inverse of the Laplace transform:

ℒ⁻¹[Y(s)]=ℒ⁻¹[ $-\frac{1}{3} \frac{2}{s^{2}+4}$ ]-ℒ⁻¹[ $2\frac{s }{s^{2}+1}$ ]+ℒ⁻¹[ $\frac{5}{3}\frac{1}{s^{2}+1}$ ]

$y(t)= - \frac{1}{3} Sin(2t)+2 Cos(t)+\frac{5}{3} Sin(t)$

3 0

3 years ago

3x-2=3<br> X=<br> Explain too please

Lubov Fominskaja [6]

3x-2=3

3x=3+2

3x=5

x=5/3

Answer : According to the information provided in the question, the value of 'x' is 5/3

5 0

3 years ago

Read 2 more answers