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3 years ago

In a class full of men and women 5/9of the class are women. What is the ratio of men to women in its

Mathematics

1 answer:

Murljashka [212]3 years ago

4 0

Answer:

The ratio in its simplest from is 4:5

Step-by-step explanation:

Now, let’s pick an arbitrary value for the total number of students in that class.

Let’s say we have 45 students in the class

The number of women would be 5/9 * 45 = 25

The number of men would be 45-25 = 20

So the ratio of men to women would be;

20:25 which in its simplest form = 4:5

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Chicago Avenue is parallel to Ontario Street what is the relationship between angles five and seven?

Triss [41]

Answer:

they are corresponding angles

6 0

3 years ago

The tensile strength of stainless steel produced by a plant has been stable for a long time with a mean of 72 kg/mm2 and a stand

Elanso [62]

Answer:

95% confidence interval for the mean of tensile strength after the machine was adjusted is [73.68 kg/mm2 , 74.88 kg/mm2].

Yes, this data suggest that the tensile strength was changed after the adjustment.

Step-by-step explanation:

We are given that the tensile strength of stainless steel produced by a plant has been stable for a long time with a mean of 72 kg/mm 2 and a standard deviation of 2.15.

A machine was recently adjusted and a sample of 50 items were taken to determine if the mean tensile strength has changed. The mean of this sample is 74.28. Assume that the standard deviation did not change because of the adjustment to the machine.

Firstly, the pivotal quantity for 95% confidence interval for the population mean is given by;

P.Q. = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\bar X$ = sample mean strength of 50 items = 74.28

$\sigma$ = population standard deviation = 2.15

n = sample of items = 50

$\mu$ = population mean tensile strength after machine was adjusted

Here for constructing 95% confidence interval we have used One-sample z test statistics as we know about population standard deviation.

So, 95% confidence interval for the population mean, $\mu$ is ;

P(-1.96 < N(0,1) < 1.96) = 0.95 {As the critical value of z at 2.5% level of

significance are -1.96 & 1.96}

P(-1.96 < $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ < 1.96) = 0.95

P( $-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ < ${\bar X-\mu}$ < $1.96 \times {\frac{\sigma}{\sqrt{n} } }$ ) = 0.95

P( $\bar X-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ < $\mu$ < $\bar X+1.96 \times {\frac{\sigma}{\sqrt{n} } }$ ) = 0.95

95% confidence interval for $\mu$ = [ $\bar X-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ , $\bar X+1.96 \times {\frac{\sigma}{\sqrt{n} } }$ ]

= [ $74.28-1.96 \times {\frac{2.15}{\sqrt{50} } }$ , $74.28+1.96 \times {\frac{2.15}{\sqrt{50} } }$ ]

= [73.68 kg/mm2 , 74.88 kg/mm2]

Therefore, 95% confidence interval for the mean of tensile strength after the machine was adjusted is [73.68 kg/mm2 , 74.88 kg/mm2].

Yes, this data suggest that the tensile strength was changed after the adjustment as earlier the mean tensile strength was 72 kg/mm2 and now the mean strength lies between 73.68 kg/mm2 and 74.88 kg/mm2 after adjustment.

8 0

3 years ago

62% of trees were saved from a fire. If this represents 1420 trees, how many trees were originally in the forest?Round to the ne

tresset_1 [31]

Answer:

2290 trees

Step-by-step explanation:

Given data

Let the total number of trees be x

62% of the total trees x is 1420 trees

mathematically

62/100x= 1420

0.62x= 1420

divide both sides by 0.62

x= 1420/0.62

x= 2290.32

To the nearest whole tree= 2290 trees

5 0

3 years ago

Please help, this is important.

STatiana [176]

Answer: B, D

Step-by-step explanation:

You Can just count the blocks

B: has 24 and D has 24 which both of them are between 30 and 20

4 0

3 years ago

Read 2 more answers

In your opinion, which step includes a mistake:

Ilya [14]

Answer:

yes Cecilia make her first mistake in step 2

8 0

2 years ago