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3 years ago

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the probabilities of having 0,1,2,3, or 4 people waiting in line at a grocery store are shown in the probability distribution be

low. what is the expected number of people waiting in line, rounded to the nearest tenth?

1 answer:

makvit [3.9K]3 years ago

8 0

Answer:

1.4

Step-by-step explanation:

Given the probability distribution :

X _____ 0 ____1 ____ 2 ____ 3 ____4

P(x) _ 0.16 _ 0.41 _ 0.32 __ 0.09 __ 0.02

Expected number of people waiting in line :

E(X) = Σ(x * p(x))

E(X) = (0*0.16) + (1*0.41) + (2*0.32) + (3*0.09) + (4*0.02)

E(X) = 1.4

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A clothing manufacturer uses the model a=f+4−−−−√−36−f−−−−−√ to estimate the amount of fabric to order from a mill. In the formu

Anit [1.1K]

Questions:

A clothing manufacturer uses the model a = √(f + 4) - √(36 - f) to estimate the amount of fabric to order from a mill. In the formula, a is the number of apparel items (in hundreds) and f is the number of units of fabric needed. If 400 apparel items will be manufactured , how many units of fabric should be ordered?

Answer:

32 units of fabrics

Step-by-step explanation:

Given

$a = \sqrt{f + 4} - \sqrt{36 - f}$

Required

Find f when a = 4

Substitute 4 for a

$4 = \sqrt{f + 4} - \sqrt{36 - f}$

Rewrite as:

$\sqrt{36 - f} + 4 = \sqrt{f + 4}$

Square both sides

$(\sqrt{36 - f} + 4)^2 = (\sqrt{f + 4})^2$

$(\sqrt{36 - f} + 4)^2 = f + 4$

$36 - f + 8\sqrt{36 - f} + 16 = f + 4$

Collect Like Terms

$8\sqrt{36 - f}= f +f+ 4 - 36 -16$

$8\sqrt{36 - f}= 2f -48$

Divide through by 2

$4\sqrt{36 - f}= f -24$

Square both sides

$16(36-f) = (f - 24)^2$

$16(36-f) = f^2 - 48f + 576$

$576-16f = f^2 - 48f + 576$

$-16f = f^2 - 48f$

Collect like terms

$f^2 - 48f + 16f = 0$

$f^2 -32f = 0$

Factorize

$f(f - 32) = 0$

$f = 0$ or $f = 32$

f can not be 0 because some units must be ordered.

So, f = 32

6 0

3 years ago

What's the difference between 5.4 x 10-7 and 7.1 x 10-8? Express your answer

vichka [17]

Answer:

.76 x 10 or 7.6 x 10^0

Step-by-step explanation:

divide coefficients and subtract exponents

5.4 / 7.1 = .76

10^-7 / 10^-8 = 10

5 0

3 years ago

What is the radius of the circle given by the equation below?

grandymaker [24]

$x^2+18x+y^2+18y=-146 \\ \\( x^2+18x + 81)+(y^2+18y+81)-81-81=-146\\ \\(x+9)^2+(y+9)^2=-146+81+81\\ \\(x+9)^2+(y+9)^2=-146+162\\ \\(x+9)^2+(y+9)^2=16$

$This \ is \ in \ the \ general \ circle \ form : (x-h)^ 2+ (y-k)^2 = r^2, so: \\ \\ r^2=16 \\ \\r=\sqrt{16}\\ \\r=4 \\ \\ Answer : \ C. 4$

8 0

4 years ago

What is the equation?

Minchanka [31]

Answer:

y - 4 = (1/3)(x - 9) or x - 3y = -3

Step-by-step explanation:

Here we're told that the slope is 1/3 and that (9, 4) is a point on the line. Use the point-slope formula y - k = m(x - h). Substitute 4 for k, 9 for h and 1/3 for m:

y - 4 = (1/3)(x - 9) (point-slope formula)

3y - 12 = x - 9 (standard form of the same equation) = >

-12 + 9 = x - 3y, or x - 3y = -3 (standard form)

8 0

3 years ago

Can someone help please

Darya [45]

Slope : 3

y - intercept : -2

Equation : y = -3x-2

7 0

3 years ago