–14, –7, 0, 7, 14, …<br> Find the 19th term…

The ratio of pencils to erasers is 4:1. if there are 20 pencils, how many erasers are there?

serious [3.7K]

5 Erasers, 4:1 is equal to 20:5, if you just multiply both numbers by 5

7 0

3 years ago

true or false If x represents a random variable with mean 114 and standard deviation 40, then the standard deviation of the samp

Goshia [24]

Answer:

$\mu = 114, \sigma = 40$

We also know that we select a sample size of n =100 and on this case since the sample size is higher than 30 we can apply the central limit theorem and the distribution for the sample mean would be given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And the standard deviation for the sampling distribution would be:

$\sigma_{\bar X}= \frac{40}{\sqrt{100}}= 4$

So then the answer is TRUE

Step-by-step explanation:

Let X the random variable of interest and we know that the true mean and deviation for this case are given by:

$\mu = 114, \sigma = 40$

We also know that we select a sample size of n =100 and on this case since the sample size is higher than 30 we can apply the central limit theorem and the distribution for the sample mean would be given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And the standard deviation for the sampling distribution would be:

$\sigma_{\bar X}= \frac{40}{\sqrt{100}}= 4$

So then the answer is TRUE

6 0

3 years ago

Prove the sum of two rational numbers is rational where a, b, c, and d are integers and b and d cannot be zero. Fill in the miss

mario62 [17]

Answer:

We conclude that the sum of two rational numbers is rational.

Hence, the fraction will be a rational number. i.e.

$\frac{ad+cb}{bd}$ ∵ b≠0, d≠0, so bd≠0

Step-by-step explanation:

Let a, b, c, and d are integers.

Let a/b and c/d are two rational numbers and b≠0, d≠0

Proving that the sum of two rational numbers is rational.

$\frac{a}{b}+\frac{c}{d}$

As the least common multiplier of b, d: bd

Adjusting fractions based on the LCM

$\frac{a}{b}+\frac{c}{d}=\frac{ad}{bd}+\frac{cb}{db}$

$\mathrm{Since\:the\:denominators\:are\:equal,\:combine\:the\:fractions}:\quad \frac{a}{c}\pm \frac{b}{c}=\frac{a\pm \:b}{c}$

$=\frac{ad+cb}{bd}$

As b≠0, d≠0, so bd≠0

Therefore, we conclude that the sum of two rational numbers is rational.

Hence, the fraction will be a rational number. i.e.

$\frac{ad+cb}{bd}$ ∵ b≠0, d≠0, so bd≠0

3 0

3 years ago

What is the slope of a line perpendicular to the line whose equation is 2x+8y -64 Fully reduce your answer.

Lelechka [254]

Answer: I am pretty sure it is y=-1/4x-8. Hope this helps!

Step-by-step explanation:subtract the 2x from both sides which gives you 8y=-2x-64. Then you want to divide both sides by 8 to get y=-1/4x-8

6 0

3 years ago

Donnie's dog had a litter of puppies. He notices that 2 are brown, 1 is white, and 3 are spotted. What is the ratio of total pup

Levart [38]

Answer:

The ratio of total puppies to brown puppies is 3 for 1. For every 3 puppies there is 1 brown puppie.

Step-by-step explanation:

In order to find the ratio between the total puppies to brown puppies we need to take the total amount of puppies , that is, the sum of all the puppies and divide it by the number of brown puppies. So we have:

ratio = total amount of puppies/brown puppies

ratio = (3+2+1)/(2) = 6/2 = 3/1

The ratio is for every three puppies we have one brown puppie.

8 0

3 years ago

–14, –7, 0, 7, 14, … Find the 19th term…