Factor each experssion. 8x+16y

In a process that manufactures bearings, 90% of the bearings meet a thickness specification. A shipment contains 500 bearings. A

Marina86 [1]

Answer:

(a) 0.94

(b) 0.20

(c) 90.53%

Step-by-step explanation:

From a population (Bernoulli population), 90% of the bearings meet a thickness specification, let $p_1$ be the probability that a bearing meets the specification.

So, $p_1=0.9$

Sample size, $n_1=500$ , is large.

Let X represent the number of acceptable bearing.

Convert this to a normal distribution,

Mean: $\mu_1=n_1p_1=500\times0.9=450$

Variance: $\sigma_1^2=n_1p_1(1-p_1)=500\times0.9\times0.1=45$

$\Rightarrow \sigma_1 =\sqrt{45}=6.71$

(a) A shipment is acceptable if at least 440 of the 500 bearings meet the specification.

So, $X\geq 440.$

Here, 440 is included, so, by using the continuity correction, take x=439.5 to compute z score for the normal distribution.

$z=\frac{x-\mu}{\sigma}=\frac{339.5-450}{6.71}=-1.56$ .

So, the probability that a given shipment is acceptable is

$P(z\geq-1.56)=\int_{-1.56}^{\infty}\frac{1}{\sqrt{2\pi}}e^{\frac{-z^2}{2}}=0.94062$

Hence, the probability that a given shipment is acceptable is 0.94.

(b) We have the probability of acceptability of one shipment 0.94, which is same for each shipment, so here the number of shipments is a Binomial population.

Denote the probability od acceptance of a shipment by $p_2$ .

$p_2=0.94$

The total number of shipment, i.e sample size, $n_2= 300$

Here, the sample size is sufficiently large to approximate it as a normal distribution, for which mean, $\mu_2$ , and variance, $\sigma_2^2$ .

Mean: $\mu_2=n_2p_2=300\times0.94=282$

Variance: $\sigma_2^2=n_2p_2(1-p_2)=300\times0.94(1-0.94)=16.92$

$\Rightarrow \sigma_2=\sqrt(16.92}=4.11$ .

In this case, X>285, so, by using the continuity correction, take x=285.5 to compute z score for the normal distribution.

$z=\frac{x-\mu}{\sigma}=\frac{285.5-282}{4.11}=0.85$ .

So, the probability that a given shipment is acceptable is

$P(z\geq0.85)=\int_{0.85}^{\infty}\frac{1}{\sqrt{2\pi}}e^{\frac{-z^2}{2}=0.1977$

Hence, the probability that a given shipment is acceptable is 0.20.

(c) For the acceptance of 99% shipment of in the total shipment of 300 (sample size).

The area right to the z-score=0.99

and the area left to the z-score is 1-0.99=0.001.

For this value, the value of z-score is -3.09 (from the z-score table)

Let, $\alpha$ be the required probability of acceptance of one shipment.

So,

$-3.09=\frac{285.5-300\alpha}{\sqrt{300 \alpha(1-\alpha)}}$

On solving

$\alpha= 0.977896$

Again, the probability of acceptance of one shipment, $\alpha$ , depends on the probability of meeting the thickness specification of one bearing.

For this case,

The area right to the z-score=0.97790

and the area left to the z-score is 1-0.97790=0.0221.

The value of z-score is -2.01 (from the z-score table)

Let $p$ be the probability that one bearing meets the specification. So

$-2.01=\frac{439.5-500 p}{\sqrt{500 p(1-p)}}$

On solving

$p=0.9053$

Hence, 90.53% of the bearings meet a thickness specification so that 99% of the shipments are acceptable.

8 0

3 years ago

Please answer this correctly

melomori [17]

Answer:

13 ft by 15 ft

Step-by-step explanation:

2x+2y=56

x+y=28

x×y=195

13+15=28

13×15=195

8 0

3 years ago

What is the value of h in the figure below?

yaroslaw [1]

Answer:

12

Step-by-step explanation:

ΔBAD is similar to ΔCBD. So we can write a proportion:

BD / CD = AD / BD

h / 16 = 9 / h

h² = 144

h = 12

5 0

3 years ago

PLEASE HELP ME.<br> THANKS!!!

Veronika [31]

Cos(x) = sin(x + 20o) Use the double cos angle formula

Cos(x) = sin(x)*cos(20) + cos(x)*sin(20) Divide through by cos(x). Tanx = sin(x)/cos(x)

1 = tan(x)*cos(20) + sin(20) Subtract sin(20) from both sides.

1 - sin(20) = tan(x)*cos(20) Calculate the value of 1 - sin(20)

0.65798 = tan(x) * 0.939692 Divide by cos(20)

tan(x) = 0.65795/0.939692

tan(x) = 0.70021 Take the inverse of 0.7) = tan(x)

x = tan-1(0.70021)

x = 35 degrees as expected.

Problem Two

The easiest way to do this is to pick random values and try it. The two acute angles are complementary. So 25 and 65 are random enough.

Let A = 25

Let C = 65

A

Tan(25) = sin(25)/sin(65) ; tan(25) = 0.4663.

sin(25)/sin(65) = 0.4663 Answer

B

Sin(90 - C) = Sin(A)

Tan(90 - A) = Tan(C)

So the question becomes Cos(A) = Tan(C) / sin(A)

Cos(25) = Tan(65)/Sin(25)

0.906 = ? 5.07 This statement isn't true.

C

Sin(65) = Cos(25)/Tan(65)

.906 = 0.4226 C is not the correct answer.

D

D isn't true. The tan does not relate that away. You can find it for yourself.

Cos(A) = Tan(C) You should get 0.906 = 2.14

E

Sin(C) = Cos(A) / Tan(A) I'll leave you to show this is wrong.

Problem 3

The diagram below is for this problem. Cos(x) = 50/100 = 0.5

x = cos-1(0.5)

x = 60 degrees.

Part 2

Sin(60) = opposite / hypotenuse

opposite = sin(60) * hypotenuse

opposite = 86.61 Be sure and round this to whatever the question says to round it to.

4 0

3 years ago

Carly drove 617.3 miles his car get about 41 miles per gallon which is the best estimate of how many gallons of gas Carly used

Lerok [7]

Answer:

He used about 15 gallons

Step-by-step explanation: if he drove 617.3 miles and he gets 41 miles per gallon, then we can use the formula 41x=617.3 to solve this formula, we would divide 617.3 by 41 to isolate x. 617.3 divided by 41 is equal to 15 and therefore x = 15

3 0

3 years ago