Solve a = D + C/B for d d = ab - c d = ab + c d = a/b

A test is used to assess readiness for college. In a recent year, the mean test score was 20.3 and the standard deviation was 4

Vlada [557]

Answer:

$\mu = 20.3$

$\sigma = 4.9$

And we can find the limits in order to consider values as significantly low and high like this:

$Low\leq \mu -2 \sigma= 20.3- 2*4.9 = 10.5$

$High\geq \mu +2 \sigma= 20.3+ 2*4.9 = 30.1$

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Solution to the problem

For this case we can consider a value to be significantly low if we have that the z score is lower or equal to - 2 and we can consider a value to be significantly high if its z score is higher tor equal to 2.

For this case we have the mean and the deviation given:

$\mu = 20.3$

$\sigma = 4.9$

And we can find the limits in order to consider values as significantly low and high like this:

$Low \leq \mu -2 \sigma= 20.3- 2*4.9 = 10.5$

$High\geq \mu +2 \sigma= 20.3+ 2*4.9 = 30.1$

6 0

3 years ago

Si el velocimetro de un auto marca un 25% mas que la verdadera velocidad y en este momento marca 100km/h entonces la velocidad v

GenaCL600 [577]

Answer:

True speed of the car is 87 km/h.

Step-by-step explanation:

Speed = 100 km/h

hike in speed = 25 %

Let the true speed is v.

$v + 15% of v = 100 \\\\v + 0.15 v = 100 \\\\1.5 v = 100\\\\ v = 87 km/h$

6 0

3 years ago

4. Diego is thinking of two positive numbers. He says, "If we triple the first number and

aleksandr82 [10.1K]

Answer:

3x + 2y = 34. and two possible pairs of positive numbers are (x, y) = (10, 2) and (x, y) = (4, 11).

Step-by-step explanation:

Let the First positive number be x and second positive number be y.

Triple of first number = 3x

double of second number = 2y

According to question,

3x + 2y = 34

Therefore, the equation is 3x + 2y = 34

So the two possible pair of numbers Diego would be thinking of must satisfy the equation 3x + 2y = 34

Now, 3x + 2y = 34

3x = 34 - 2y

Let x = 10 and by substituting its value in above expression,

$3 \times 10 = 34 - 2y$

$30 = 34 - 2y$

$2y = 34 - 30$

$2y = 4$

$y = 2$

Therefore first pair (x, y) = (10, 2)

In the same way put x = 4 then,

3x = 34 - 2y

$3 \times 4 = 34 - 2y$

$2y = 34 - 12$

$2y = 22$

$y = 11$

Therefore first pair (x, y) = (4, 11)

Therefore, (x, y) = (4, 11) and (x, y) = (10, 2) are the two possible pairs of numbers Diego could be thinking of as these both values satisfy the equation 3x + 2y = 34.

8 0

3 years ago

Which function is graphed below?

lys-0071 [83]

Answer: The second option, y = 3(1/3)^x

Step-by-step explanation: Input each equation into a graphing calculator (preferably GeoGebra online) and check the answer. I linked the equation, but make sure to check anyway just in case :)

7 0

2 years ago

Our difference is 12. Our product is 81. What are the two numbers.

Delicious77 [7]

16.81665382639196787 x 4.81665382639196787

80.99999999999999982646270300946414412

All you have to do is figure out the rest of the decimal places. I couldn't go any farther. Good luck!

7 0

3 years ago

Solve a = D + C/B for d d = ab - c d = ab + c d = a/b - c