Need answer ASAP please help

Which of the following of x makes the rational expressions below undefined

alisha [4.7K]

A rational expression is undefined if the denominator is zero. Since the denominator is $x+13$ , the expression is undefined if

$x+13 = 0 \iff x=-13$

5 0

2 years ago

If the federal reserve sells 70,000 in treasury bonds to a bank at 9% interest, what is the immediate effect on the money supply

taurus [48]

D , - if the Fed sells bonds, it decreases the money supply by removing cash from the economy in exchange for bonds.
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5 0

3 years ago

The wavelength of red light in a spectrum is about 0.0000007 meters. Which

Nana76 [90]

Answer:

$0.0000007$

And if we count the number of zeros before the number 7, we can rewrite the number like this:

$7x10^{-7}$

We cansolve this problem also counting the number of positions that we need to move the decimal point to the right in order to obtain the first number (7)

And the best option would be:

B. 7 x 10-7

Step-by-step explanation:

For this case we have the following number given:

$0.0000007$

And if we count the number of zeros before the number 7, we can rewrite the number like this:

$7x10^{-7}$

We cansolve this problem also counting the number of positions that we need to move the decimal point to the right in order to obtain the first number (7)

And the best option would be:

B. 7 x 10-7

8 0

2 years ago

A carpenter has a piece of wood that is 78 inches long. He wants to cut it so that one piece is five times as long as the other

Lyrx [107]

Answer:

13 and 65

Step-by-step explanation:

x + 5x = 78

(because u want a piece (x) and a piece that's five times longer than x- so 5x. and they should come from a 78 inch piece)

6x = 78

x = 78 / 6

x= 13

(to counter check: 13 * 5 = 65.

65 + 13 = 78 )

7 0

3 years ago

Read 2 more answers

A company surveyed 2400 men where 1248 of the men identified themselves as the primary grocery shopper in their household. a) E

polet [3.4K]

Answer:

a) With a confidence level of 98%, the percentage of all males who identify themselves as the primary grocery shopper are between 0.4962 and 0.5438.

b) The lower limit of the confidence interval is higher that 0.43, so if he conduct a hypothesis test, he will find that the data shows evidence to said that the fraction is higher than 43%.

c) $\alpha =1-0.98=0.02$

Step-by-step explanation:

If np' and n(1-p') are higher than 5, a confidence interval for the proportion is calculated as:

$p'-z_{\alpha/2}\sqrt{\frac{p'(1-p')}{n} }\leq p\leq p'+z_{\alpha/2}\sqrt{\frac{p'(1-p')}{n} }$

Where p' is the proportion of the sample, n is the size of the sample, p is the proportion of the population and $z_{\alpha/2}$ is the z-value that let a probability of $\alpha/2$ on the right tail.

Then, a 98% confidence interval for the percentage of all males who identify themselves as the primary grocery shopper can be calculated replacing p' by 0.52, n by 2400, $\alpha$ by 0.02 and $z_{\alpha/2}$ by 2.33

Where p' and $\alpha$ are calculated as:

$p' = \frac{1248}{2400}=0.52\\\alpha =1-0.98=0.02$

So, replacing the values we get:

$0.52-2.33\sqrt{\frac{0.52(1-0.52)}{2400} }\leq p\leq 0.52+2.33\sqrt{\frac{0.52(1-0.52)}{2400} }\\0.52-0.0238\leq p\leq 0.52+0.0238\\0.4962\leq p\leq 0.5438$

With a confidence level of 98%, the percentage of all males who identify themselves as the primary grocery shopper are between 0.4962 and 0.5438.

The lower limit of the confidence interval is higher that 0.43, so if he conduct a hypothesis test, he will find that the data shows evidence to said that the fraction is higher than 43%.

Finally, the level of significance is the probability to reject the null hypothesis given that the null hypothesis is true. It is also the complement of the level of confidence. So, if we create a 98% confidence interval, the level of confidence $1-\alpha$ is equal to 98%

It means the the level of significance $\alpha$ is:

$\alpha =1-0.98=0.02$

4 0

3 years ago