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3 years ago

If Olivia has 68,79, and 74 for his 3 tests, what must he get on his 4th test in order to have an 80 average?

1 answer:

3 0

The other person did not explain so I will:
(68+79+74)= 221/3 =73.7
80 x 4 = 320
320-221 = 99
He must get 99 on his 4th test.
Thanks

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Dan uses the equation g(x)=5x+50 to model the balance of his savings account after saving for x weeks. What is the value and mea

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Answer:

D. $350

Step-by-step explanation:

Replace 'x' with 60. g(60)= 5(60) =+ 50

g(60)= 300 + 50

g(60) = 350.

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3 years ago

Estimate the solution to the system of equations.<br><br> y=−2x−5 <br> y=2x−2

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Answer:

(-3/4, -7/2)

Step-by-step explanation:

y= −2x − 5

y= 2x − 2

2y = -7

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-7/2 = 2x - 2

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3 years ago

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What is the reduced fraction form of 0.2

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Answer: 0.2 reduced as a fraction 1/5

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3 years ago

Claim: Fewer than 94% of adults have a cell phone. In a reputable poll of 1004 adults, 86% said that they have a cell phone.

meriva

Answer: The value of test statistic = -10.67

Step-by-step explanation:

Test statistic for proportion:

$z=\dfrac{\hat{p}-p}{\sqrt{\dfrac{p(1-p)}{n}}}$

, where p= population proportion

n= sample size

$\hat{p}$ = sample proportion

AS per given,

p=0.94, n= 1004, $\hat{p}=0.86$

$z=\dfrac{0.86-0.94}{\sqrt{\dfrac{0.94(1-0.94)}{1004}}}\\\\=\dfrac{-0.08}{\sqrt{\dfrac{0.0564}{1004}}}\\\\=\dfrac{-0.08}{\sqrt{0.0000561752988048}}\\\\=\dfrac{-0.08}{0.00749501826581}\\\\=-10.673756509\approx-10.67$

i.e. the value of test statistic = -10.67

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3 years ago

The length of a rectangle is 5 inches more than its vedth. The area of the rectangle is equal to

jarptica [38.1K]

Answer:

The width = x = 14

The length = x+5 = 14+5 = 19

Step-by-step explanation:

Let l = length, w = width, A = area = l×w , and P = perimeter = 2(l+w)

Let 'x' be the width

As the length 'l' of a rectangle is 5 inches more than its width.

so the length will be = x+5

As the Area of the rectangle is equal to 2 inches more than 4 times the perimeter.

A = 4P + 2

so the equation becomes

l × w = 4×2(l+w)+2

substituting w=x, l = x+5,

(x+5)x = 8(x+5+x)+2

x²+5x = 8(5+2x)+2

x²+5x = 40+16x+2

x²+5x = 16x+42

x²+5x-16x-42 =0

x²-11x-42=0

$x^2-11x=42$

$\mathrm{Add\:}a^2=\left(-\frac{11}{2}\right)^2\mathrm{\:to\:both\:sides}$

$x^2-11x+\left(-\frac{11}{2}\right)^2=42+\left(-\frac{11}{2}\right)^2$

$x^2-11x+\left(-\frac{11}{2}\right)^2=\frac{289}{4}$

$\left(x-\frac{11}{2}\right)^2=\frac{289}{4}$

$\mathrm{For\:}f^2\left(x\right)=a\mathrm{\:the\:solutions\:are\:}f\left(x\right)=\sqrt{a},\:-\sqrt{a}$

solving

$x-\frac{11}{2}=\sqrt{\frac{289}{4}}$

$x-\frac{11}{2}=\frac{\sqrt{289}}{\sqrt{4}}$

$x-\frac{11}{2}=\frac{\sqrt{289}}{2}$

$x-\frac{11}{2}=\frac{17}{2}$

$x-\frac{11}{2}+\frac{11}{2}=\frac{17}{2}+\frac{11}{2}$

$x=14$

similarly solving

$x-\frac{11}{2}=-\sqrt{\frac{289}{4}}$

$x-\frac{11}{2}=-\frac{17}{2}$

$x-\frac{11}{2}+\frac{11}{2}=-\frac{17}{2}+\frac{11}{2}$

$x=-3$

x = 14, or x = -3

As the width 'x' can not be negative.

so x = 14

Thus,

The width = x = 14

The length = x+5 = 14+5 = 19

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3 years ago