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3 years ago

Camison's minnan gets 14 miles per gallon for city driving and 19 miles per gan

Mathematics

1 answer:

loris [4]3 years ago

3 0

Answer:

7 gallons were used for city driving and 17 gallons were used for highway driving

Correct statement and question:

camison's minnan gets 14 miles per gallon for city driving and 19 miles per gallon for highway driving. At the beginning of the week, the 24-gallon tank was full. The family traveled 421 miles before running out of gas. How many gallons were used for city driving and how many were used for highway driving?

Source:

Previous question found at brainly

Step-by-step explanation:

x = Gallons for city driving

24 - x = Gallons for highway driving

Miles drove before running out of gas = 421

Now let's solve for x, writing the following equation:

14x + 19 (24 - x) = 421

14x + 456 - 19x = 421

-5x = 421 - 456

-5x = - 35

x = -35/-5

x = 7 ⇒ 24 -x = 17

7 gallons were used for city driving and 17 gallons were used for highway driving

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If ΔABC ≅ ΔDEF, then what corresponding parts are congruent?

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Answer:

its A.

Step-by-step explanation:

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2 years ago

A certain geneticist is interested in the proportion of males and females in the population who have a minor blood disorder. In

lord [1]

Answer:

95% confidence interval for the difference between the proportions of males and females who have the blood disorder is [-0.064 , 0.014].

Step-by-step explanation:

We are given that a certain geneticist is interested in the proportion of males and females in the population who have a minor blood disorder.

A random sample of 1000 males, 250 are found to be afflicted, whereas 275 of 1000 females tested appear to have the disorder.

Firstly, the pivotal quantity for 95% confidence interval for the difference between population proportion is given by;

P.Q. = $\frac{(\hat p_1-\hat p_2)-(p_1-p_2)}{\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ ~ N(0,1)

where, $\hat p_1$ = sample proportion of males having blood disorder= $\frac{250}{1000}$ = 0.25

$\hat p_2$ = sample proportion of females having blood disorder = $\frac{275}{1000}$ = 0.275

$n_1$ = sample of males = 1000

$n_2$ = sample of females = 1000

$p_1$ = population proportion of males having blood disorder

$p_2$ = population proportion of females having blood disorder

Here for constructing 95% confidence interval we have used Two-sample z proportion statistics.

So, 95% confidence interval for the difference between the population proportions, ( $p_1-p_2$ ) 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 < $\frac{(\hat p_1-\hat p_2)-(p_1-p_2)}{\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ < 1.96) = 0.95

P( $-1.96 \times {\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ < ${(\hat p_1-\hat p_2)-(p_1-p_2)}$ < $1.96 \times {\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ ) = 0.95

P( $(\hat p_1-\hat p_2)-1.96 \times {\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ < ( $p_1-p_2$ ) < $(\hat p_1-\hat p_2)+1.96 \times {\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ ) = 0.95

95% confidence interval for ( $p_1-p_2$ ) =

[ $(\hat p_1-\hat p_2)-1.96 \times {\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ , $(\hat p_1-\hat p_2)+1.96 \times {\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+ \frac{\hat p_2(1-\hat p_2)}{n_2}} }$ ]

= [ $(0.25-0.275)-1.96 \times {\sqrt{\frac{0.25(1-0.25)}{1000}+ \frac{0.275(1-0.275)}{1000}} }$ , $(0.25-0.275)+1.96 \times {\sqrt{\frac{0.25(1-0.25)}{1000}+ \frac{0.275(1-0.275)}{1000}} }$ ]

= [-0.064 , 0.014]

Therefore, 95% confidence interval for the difference between the proportions of males and females who have the blood disorder is [-0.064 , 0.014].

8 0

3 years ago

The weight of an organ in adult males has a bell shaped distribution with a mean of 320 grams and a standard deviation of 20 gra

Stells [14]

Answer:

a) 300 and 340

b) 95%

c) 5%

d) 81.5%

Step-by-step explanation:

Weight of an organ in adult males has a bell shaped(normal distribution).

Mean weight = 320 grams

Standard deviation = 20 grams

Part a) About 68% of organs weight between:

According to the empirical rule:

68% of the data values lie within 1 standard deviation of the mean
95% of the data values lie within 2 standard deviation of the mean
99.7% of the data values lie within 3 standard deviation of the mean

Thus, 68% of the data values lie in the range: Mean - 1 standard deviation to Mean + 1 Standard Deviation.

Using the values of Mean and Standard deviation, we get:

Mean - 1 Standard Deviation = 320 - 20 = 300 grams

Mean + 1 Standard Deviation = 320 + 20 = 340 grams

This means 68% of the organs will weigh between 300 and 340 grams.

Part b) What percentage of organs weighs between 280 grams and 360 grams?

In order to find what percentage of organs weight between the given range, we need to find how much far these values are from the mean.

Since, mean is 320 and 280 is 40 less than mean, we can write:

280 = 320 - 40

280 = 320 - 2(2)

280 = 320 - 2 Standard Deviations

Similarly,

360 = 320 + 40

360 = 320 + 2 Standard Deviations

So, we have to tell what percentage of values lie within 2 standard deviation of the mean. According to the empirical law, this amount is 95%.

So, 95% of the organs weigh between 280 grams and 360 grams.

Part c) What percentage of organs weighs less than 280 grams or more than 360 grams?

From the previous part we know that 95% of the organs weight between 280 grams and 360 grams.

It is given that the distribution is bell shaped. The total percentage under a bell shaped distribution is 100%. So in order to calculate how much percentage of values are below 280 and above 360, we need to subtract the percentage of values that are between 280 and 360 from 100% i.e.

Percentage of Value outside the range = 100% - Percentage of values inside the range

So,

Percentage of organs weighs less than 280 grams or more than 360 grams = 100 - Percentage of organs that weigh between 280 grams and 360 grams

Percentage of organs weighs less than 280 grams or more than 360 grams = 100% - 95%

= 5%

So, 5% of the organs weigh less than 280 grams or more than 360 grams.

Part d) Percentage of organs weighs between 300 grams and 360 grams.

300 is 1 standard deviation below the mean and 360 is 2 standard deviations above the mean.

Previously it has been established that, 68% of the data values lie within 1 standard deviation of the mean i.e

From 1 standard deviation below the mean to 1 standard deviation above the mean, the percentage of values is 68%. Since the distribution is bell shaped and bell shaped distribution is symmetric about the mean, so the percentage of values below the mean and above the mean must be the same.

So, from 68% of the data values that are within 1 standard deviation from the mean, half of them i.e. 34% are 1 standard deviation below the mean and 34% are 1 standard deviation above the mean. Thus, percentage of values from 300 to 320 is 34%

Likewise, data within 2 standard deviations of the mean is 95%. From this half of the data i.e. 47.5% is 2 standard deviations below the mean and 47.5% is 2 standard deviations above the mean. Thus, percentage of values between 320 and 360 grams is 47.5%

So,

The total percentage of values from 300 grams to 360 grams = 34% + 47.5% = 81.5%

Therefore, 81.5% of organs weigh between 300 grams and 360 grams

6 0

2 years ago

Which statement is true of this function?

Eduardwww [97]

Answer:

A. As the value of x increases, the value of f(x) moves toward a constant

Step-by-step explanation:

An exponential function with a base less than 1 will decay to zero. Here, the exponential has -2 added to it, so the decay is toward the value -2.

An exponential function is defined for all real numbers. This one has a y-intercept of -1.

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2 years ago

The scores awarded to 25 students for an assignment were as follows

Kisachek [45]

Answer:

The numbers less than 50 (A) = 4

Total numbers (S) = 14

Probability students below 50 = 4÷14

Step-by-step explanation:

That is the correct answer of it.

3 0

1 year ago