Ask question

Ask question

All categories

3 years ago

12

The life of light bulbs is distributed normally. the standard deviation of the lifetime is 25 hours and the mean lifetime of a b

ulb is 590 hours. find the probability of a bulb lasting for at most 622 hours. round your answer to four decimal places.

1 answer:

Dominik [7]3 years ago

4 0

The probability is 0.8997.

We will use a z-score to answer this question. z-scores are given by the formula
$z=\frac{X-\mu}{\sigma}$

With our information, we have
$z=\frac{622-590}{25}=\frac{32}{25}=1.28$

Looking this up in a z-table (http://www.z-table.com) we see that the area to the left of this (everything less than, up to this value) is 0.8997.

You might be interested in

What is the total number of rabbits in the neighborhood in year 2

lawyer [7]

Answer:

6

Step-by-step explanation:

5 0

3 years ago

A leather vest multiplied vero 0.63 by 1.8 point what is the correct product

labwork [276]

The answers of the product is 1.8 * 0.63 = 1.134

4 0

3 years ago

Complete the assignment on a separate sheet of paper<br><br> Please attach pictures of your work.

Irina18 [472]

Answer:

<u>TO FIND :-</u>

Length of all missing sides.

<u>FORMULAES TO KNOW BEFORE SOLVING :-</u>

$\sin \theta = \frac{Side \: opposite \: to \: \theta}{Hypotenuse}$
$\cos \theta = \frac{Side \: adjacent \: to \: \theta}{Hypotenuse}$
$\tan \theta = \frac{Side \: opposite \: to \: \theta}{Side \: adjacent \: to \: \theta}$

<u>SOLUTION :-</u>

1) θ = 16°

Length of side opposite to θ = 7

Hypotenuse = x

$=> \sin 16 = \frac{7}{x}$

$=> \frac{7}{x} = 0.27563......$

$=> x = \frac{7}{0.27563....} = 25.39568.....$ ≈ 25.3

2) θ = 29°

Length of side opposite to θ = 6

Hypotenuse = x

$=> \sin 29 = \frac{6}{x}$

$=> \frac{6}{x} = 0.48480......$

$=> x = \frac{6}{0.48480....} = 12.37599.....$ ≈ 12.3

3) θ = 30°

Length of side opposite to θ = x

Hypotenuse = 11

$=> \sin 30 = \frac{x}{11}$

$=> \frac{x}{11} = 0.5$

$=> x = 0.5 \times 11 = 5.5$

4) θ = 43°

Length of side adjacent to θ = x

Hypotenuse = 12

$=> \cos 43 = \frac{x}{12}$

$=> \frac{x}{12} = 0.73135......$

$=> x = 12 \times 0.73135.... = 8.77624....$ ≈ 8.8

5) θ = 55°

Length of side adjacent to θ = x

Hypotenuse = 6

$=> \cos 55 = \frac{x}{6}$

$=> \frac{x}{6} = 0.57357......$

$=> x = 6 \times 0.57357.... = 3.44145....$ ≈ 3.4

6) θ = 73°

Length of side adjacent to θ = 8

Hypotenuse = x

$=> \cos 73 = \frac{8}{x}$

$=> \frac{8}{x} = 0.29237......$

$=> x = \frac{8}{0.29237.....} = 27.36242.....$ ≈ 27.3

7) θ = 69°

Length of side opposite to θ = 12

Length of side adjacent to θ = x

$=> \tan 69 = \frac{12}{x}$

$=> \frac{12}{x} = 2.60508......$

$=> x = \frac{12}{2.60508....} = 4.60636....$ ≈ 4.6

8) θ = 20°

Length of side opposite to θ = 11

Length of side adjacent to θ = x

$=> \tan 20 = \frac{11}{x}$

$=> \frac{11}{x} = 0.36397......$

$=> x = \frac{11}{0.36397....} =30.22225....$ ≈ 30.2

5 0

3 years ago

Can someone help me with these both

Anna [14]

Hello,
so all you have to do is match the abbreviations to the triangles. The abbreviations stand for what is the SAME in both triangles, denoted by similar markings on equal sides and angles.

Abbreviations:
SSS = Side-Side-Side
SAS = Side-Angle-Side
ASA = Angle-Side-Angle
AAS = Angle-Angle-Side
HL = Hypotenuse-Leg

* Note - the angle side angle must go around the triangle in that order. ASA has the side BETWEEN the congruent angles.. SSA does NOT work.

(9.) ASA
(10.) AAS
(11.) SSS
(12.) No way to tell if congruent. (only 3 angles no side)
(13.) ASA
(14.) SAS
(15.) HL

7 0

3 years ago

Find the domain and range of the following graph.

shutvik [7]

Remember that the <em>domain</em> is the set of all the x terms.

So in the graph shown here, notice that the x terms seem to be increasing in both a positive and negative direction and there seems to be no limit to how large or how small the x terms can get. So the x terms can be all positive and negative numbers, including decimals and fractions.

In other words, the x terms can be All Real Numbers.

So the domain is equal to the set of all real numbers or <em>R</em>.

The range is the set of all the y terms.

Notice that all the y terms are less than or equal to 9.

So the range is {y: y ≤ 9}.

8 0

3 years ago