Order of Ope 1) 9 + ( 9 + (10 - 4)2) at(atst 2) 9 +(10 + (11

The distribution of resistance for resistors of a certain type is known to be normal, with 10% of all resistors having a resista

baherus [9]

Answer:

The mean is 9.65 ohms and the standard deviation is 0.2742 ohms.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

10% of all resistors having a resistance exceeding 10.634 ohms

This means that when X = 10.634, Z has a pvalue of 1-0.1 = 0.9. So when X = 10.634, Z = 1.28.

$Z = \frac{X - \mu}{\sigma}$

$1.28 = \frac{10.634 - \mu}{\sigma}$

$10.634 - \mu = 1.28\sigma$

$\mu = 10.634 - 1.28\sigma$

5% having a resistance smaller than 9.7565 ohms.

This means that when X = 9.7565, Z has a pvalue of 0.05. So when X = 9.7565, Z = -1.96.

$Z = \frac{X - \mu}{\sigma}$

$-1.96 = \frac{9.7565 - \mu}{\sigma}$

$9.7565 - \mu = -1.96\sigma$

$\mu = 9.7565 + 1.96\sigma$

We also have that:

$\mu = 10.634 - 1.28\sigma$

So

$10.634 - 1.28\sigma = 9.7565 + 1.96\sigma$

$1.96\sigma + 1.28\sigma = 10.645 - 9.7565$

$3.24\sigma = 0.8885$

$\sigma = \frac{0.8885}{3.24}$

$\sigma = 0.2742$

The mean is

$\mu = 10.634 - 1.28\sigma = 10 - 1.28*0.2742 = 9.65$

The mean is 9.65 ohms and the standard deviation is 0.2742 ohms.

8 0

3 years ago

Tel wether the relationship is proportional relationship. Explain why or why not.

dem82 [27]

Yes because it is linear, also if you set up the proportion 2/4=1/2 they are equal.

8 0

2 years ago

The product of 7 and x is less than or equal to -21

Mars2501 [29]

Answer:

x needs to be smaller or equal to -3

Step-by-step explanation:

-3x7 = -21

you get there by dividing -21 by 7

example smaller number: -4x7 = -28

4 0

2 years ago

Read 2 more answers

Three spherical balls with radius r are contained in a rectangular box. two of the balls are each touching 5 sides of the rectan

olganol [36]

Answer:

The volume of the space between the balls and the rectangular box is $4r^{3}(6 - \pi)$

Step-by-step explanation:

The attachment below shows the description of the rectangular bow and the three spherical balls.

From the description,

Two of the balls are each touching 5 sides of the rectangular box, say the 5 sides touched by one of the balls are sides 1,2,3,4, and 5; then the other ball will touch sides 2,3,4,5, and 6).
The middle ball also touches four sides of the rectangular box, These four sides touched by the middle ball will be sides 2,3,4, and 5.

This means the balls are tightly fitted into the rectangular box.

Each of the balls has a radius r

Hence, The volume of one of the balls is given by the volume of a sphere

$Volume of a sphere = \frac{4}{3} \pi r^{3} \\$