Solve the equation using the zero product principle (x-3)(x+6)=0

ElenaW [278]

1. C
2.A
3.D
4. B These are the only math problems I can actually do because they're more like puzzles than anything.

8 0

3 years ago

Each of the following situations describes a normally distributed population for which a statistical procedure should be used. M

densk [106]

Answer:

(a) Correct option (1).

(b) Correct option (3).

(c) Correct option (2).

Step-by-step explanation:

A one-sample z-test for mean is used to determine whether the claimed value of mean is significant or not. To perform this test we can also use the t-distribution.

The t-test is used if the following conditions are given:

The population is normally distributed
The population standard deviation is not known
The sample selected is large enough.

Similarly the (1 - α)% confidence interval for population mean can be computed either using the z-interval or the t-interval.

The same conditions should be applied to use the t-interval.

(a)

In the first case, Gale wants to determine the likely range of weight of whole coffee beans from her trusty two-tablespoon scoop to create a reliable method of brewing the perfect cup of coffee.

She selects a sample of n = 15 scoops and perform the test.

Since the population standard deviation is not known and Gale wants to know the range of weight of whole coffee beans , she should use a one sample t-confidence interval for a mean.

The correct option is (1).

(b)

In the second case, Tanya wants to determine whether the mean IQ score is at least 112 or not.

She selects a a random sample n = 20 composers and compute the statistic to perform the one-sample test.

Since the population standard deviation is not known, Tanya should use one sample t-test for a mean.

The correct option is (3).

(c)

In the second case, Jason wants to estimate what the balance of his retirement account will be in one month.

He selects the data from 1950 to 2015 and calculates this index has had an average monthly return of 0.69% with a standard deviation of 4.15%.

Now, the sample selected is quite large. The Central limit theorem can be used to approximate the sampling distribution of sample mean.

Then, $\bar X\sim N(\mu_{\bar x}, \sigma_{\bar x})$

So, Jason can use the one sample z-test for a mean to determine the balance of his retirement account will be in one month.

The correct option is (2).

7 0

4 years ago

(4) Please I need helppp

ladessa [460]

Answer:

E

Step-by-step explanation:

E is the correct answer

5 0

3 years ago

Elizabeth has $10, $5, and $1 bills worth $101. she has five more five dollar bills than ten dollar bills and 4 times more 1 dol

vesna_86 [32]

Let x be number of $10 dollar bills

Let y be number of $5 dollar bills

Let z be number of $1 dollar bills

From the question, we can come up with three equations (so we can find the values of x, y & z) :

10x + 5y + z = 101
y - x = 5
z = 4x

The first equation comes from finding the total money Elizabeth has, which is $101.

The second equation comes from value of y (number of $5 bills) is more than value of x (number of $10 bills) by 5 dollars.

The third equation comes from the value of z (number of $1 bills) being 4 times more than the value of x (number of $10 bills).

Now, we will begin to find the value of x, y & z.

From the first equation,

10x + 5y + z = 101

Substitute the third equation (z = 4x) into z:

10x + 5y + 4x = 101

Simplify this and you get,

14x + 5y = 101

Now, we use the second equation. The second equation is y - x = 5. If we try to make y as the subject, it becomes y = 5 + x.

Now, substitute this into the value of y of the last working we did:

14x + 5(5+x) = 101

Simplify that and it becomes:

x = 4

Then, substitute this value of x into the second and third equations to find y and z.

y - x = 5

y - 4 = 5

y = 9

z = 4x

z = 4(4)

z = 16

Finally, let's check these answers by substituting them into the first equation to try and see if the total value is really $101.

10x + 5y + z = 10(4) + 5(9) + 16

10x + 5y + z = 40 + 45 + 16

10x + 5y + z = 101

Thus, our answers are correct. Elizabeth has FOUR $10 bills, NINE $5 bills and SIXTEEN $1 bills.

6 0

3 years ago

Read 2 more answers

The number five added to the product of 8 and -9 is what number? The number is___

Nataly_w [17]

Answer:

-67

Step-by-step explanation:

8 x -9 = -72 + 5 = -67

6 0

3 years ago

Read 2 more answers