Ask question

Ask question

All categories

3 years ago

11

Sara bought an $11 mop and 6 sponges. She spend a total of $20. Each sponge coat the same amount. Write an equation that can be

used to find x, the cost in dollars, of each sponge

1 answer:

Reptile [31]3 years ago

4 0

Answer:

6x+11=20

x= 1.5

You might be interested in

The smaller triangle was dilated to form the larger triangle. What is the value of x?

strojnjashka [21]

Answer:

The value of x is 14

Step-by-step explanation:

The value of x is 14 because the smaller triangle was dilated by 3 to get the bigger triangle. I figured this out because

9 ÷ 3 = 3

so this would mean that 5 was dilated by 3 also. So to figure this out, it would be

5 × 3 = 15

1 of that 15 is already there.

So this means that

15-1=14

A=14

I hope this helps you.

5 0

3 years ago

Read 2 more answers

Jack usually mows his lawn in 6 hours. marilyn can mow the same yard in 4 hours. How much time would it take for them to mow the

Anuta_ua [19.1K]

Answer:

2.4 hours or 2 hours and 24 minutes

Step-by-step explanation:

Jack mows 1/6 of the lawn per hour while Marilyn mows 1/4 of the lawn together. Adding up those rates yields in their combined mowing rate:

$R = \frac{1}{6}+ \frac{1}{4}\\R=\frac{10}{24}$

The time required for them to mow the entire lawn is:

$t = \frac{1}{R}\\t = \frac{1*24}{10}\\ t=2.4\ hours$

It would take them both 2.4 hours to mow the lawn together.

5 0

2 years ago

What is x and the measurements?

nikitadnepr [17]

Answer:

see explanation

Step-by-step explanation:

The perimeter is the sum of the measures of the 3 sides.

Sum the sides and equate to 75, that is

2x - 9 + 3x + 4 + 2x + 3 = 75, that is

7x - 2 = 75 ( add 2 to both sides )

7x = 77 ( divide both sides by 7 )

x = 11

Thus

AB = 2x - 9 = 2(11) - 9 = 22 - 9 = 13 m

BC = 3x + 4 = 3(11) + 4 = 33 + 4 = 37 m

AC = 2x + 3 = 2(11) + 3 = 22 + 3 = 25 m

7 0

3 years ago

Read 2 more answers

What is six times more than three times a number is that number increased by 24. Find the number. Write an equation. And find x

Lubov Fominskaja [6]

Given the information, you can only write an expression and simplify it:

6(3(x+24))

6(3x+72)

SOlution: 18x+432

I hope I helped you with your solution! If you could give me brainliest, I would be very thankful!

4 0

3 years ago

A researcher reports survey results by stating that the standard error of the mean is 25 the population standard deviation is 40

bezimeni [28]

Answer:

a) A sample of 256 was used in this survey.

b) 45.14% probability that the point estimate was within ±15 of the population mean

Step-by-step explanation:

This question is solved using the normal probability distribution and the central limit theorem.

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

a. How large was the sample used in this survey?

We have that $s = 25, \sigma = 400$ . We want to find n, so:

$s = \frac{\sigma}{\sqrt{n}}$

$25 = \frac{400}{\sqrt{n}}$

$25\sqrt{n} = 400$

$\sqrt{n} = \frac{400}{25}$

$\sqrt{n} = 16$

$(\sqrt{n})^2 = 16^2[tex][tex]n = 256$

A sample of 256 was used in this survey.

b. What is the probability that the point estimate was within ±15 of the population mean?

15 is the bounds with want, 25 is the standard error. So

Z = 15/25 = 0.6 has a pvalue of 0.7257

Z = -15/25 = -0.6 has a pvalue of 0.2743

0.7257 - 0.2743 = 0.4514

45.14% probability that the point estimate was within ±15 of the population mean

3 0

3 years ago