Please help!!!! I'm terrible at algebra and I need your help!!!

Printed circuit cards are placed in a functional test after being populated with semiconductor chips. A lot contains 140 cards,

Ray Of Light [21]

Answer:

The probability that at least 1 defective card is in the sample is $0.9644$

Step-by-step explanation:

Here

N = 140

and n = 20

We will use the below given formula

P(at least 1 defective) = 1 - P( 0 defectives)

P( 0 defectives) =

$= \frac{^{20}C_0 * ^{120}C_{20}}{ ^{140}C_{20}}\\= 0.0356 1-0.0356 \\= 0.9644$

5 0

3 years ago

An apple orchard has an average yield of 36 bushels of apples per tree if tree density is 26 trees per acre. For each unit incre

Rama09 [41]

Answer:

4 trees per acre

Step-by-step explanation:

Given,

The original number of apples per tree = 36 bushels,

Original density of a tree = 26 per acre,

Since, for each decrease in tree density, the yield increases by 2 bushels per tree.

Let x be the number of units decreased in tree density,

So, new density = 26 - x,

New number of apples = 36 + 2x

Thus, the total yield would be,

P(x) = Number of apples per tree × density of a tree

⇒ P(x) = (26 - x)(36 + 2x)

⇒ P(x) = 936 + 52x - 36x - 2x²,

⇒ P(x) = 936 + 16x - 2x²

Differentiating with respect to x,

P'(x) = 16 - 4x

Again differentiating with respect to x,

P''(x) = -4

For maxima or minima,

P'(x) = 0

⇒ 16 - 4x = 0

⇒ -4x = -16

⇒ x = 4

For x = 4, P''(x) = negative,

Hence, 4 trees per acre should be planted to maximize the yield.

3 0

3 years ago

The partial pressure of oxygen PaO2 is a measure ofthe amount of oxygen in the blood. Assume that the distribution ofPaO2 levels

Rus_ich [418]

Answer: a) 0.8665

b) 0.8190

Step-by-step explanation:

Given : The partial pressure of oxygen PaO2 is a measure ofthe amount of oxygen in the blood. Assume that the distribution ofPaO2 levels among newborns has a $\mu=$ 38 mmHg and $\sigma=$ 9 mmHg.

If we take a random sample n= 25 newborns, then using formula $z=\dfrac{x-\mu}{\dfrac{\sigma}{\sqrt{n}}}$ , we have

At x= 36

$z=\dfrac{36-38}{\dfrac{9}{\sqrt{25}}}\approx-1.11$

At x= 41

$z=\dfrac{36-38}{\dfrac{9}{\sqrt{25}}}\approx1.67$

Using table for z-values, the probability that the sample mean will be greater than 36 :

$P(z>-1.11)=1-P(\leq-1.11)=1-(1-P(z\leq1.11))=P(z\leq1.11)=0.8665004\approx0.8665$

The probability that the sample mean will be between 36 and 41 :-

$P(-1.11$

4 0

3 years ago

The square below represents one whole.

zaharov [31]

Answer:

6 percent

Step-by-step explanation:

6/100 is shaded. This is the same thing as 0.06. Once I move the decimal two places to the right, I get 6. (I move the decimal place because percents are out of 100, so two decimal places.) This means 6 percent.

4 0

3 years ago

Help with those three please!!

Scilla [17]

Answer:

Part 1) Option A. The axis of symmetry is x=4

Part 2) Option C. minimum

Part 3) Option A. (4,-4)

Part 4) Option B. (2,0) and (6,0)

Step-by-step explanation:

we have

$f(x)=x^{2}-8x+12$