I need the answer or thos problem <br> -n+(-4)-(-4n)+6

On a map,1 in. represents 12 mi. Two cities are 6 1/2 in. on a map. How far apart are the actual cities? A. 78 mi B. 72 1/2 mi C

Dovator [93]

1 inch= 12 miles

Multiply 6 1/2 inches by total number of miles per 1 inch (12).

= 6 1/2 * 12
convert to improper fraction

= 13/2 * 12
multiply numerators

= (13*12)/2
multiply in parentheses

= 156/2
divide

= 78 miles

ANSWER: (A) 78 miles

Hope this helps! :)

3 0

3 years ago

How to simplify a mixed number

Mumz [18]

Okay I will have an example for you. 3 and 2/7. STEP 1) multiply the denominator by the whole number. 3×7=21. STEP 2) add the numerator to 21. 21+2=23. STEP 3) 23 is the new numerator so put 23 over 7. FINAL SOLUTION 23/7.

6 0

3 years ago

2 3/4 divided by 4 1/8

DochEvi [55]

Answer:

2/3

Step-by-step explanation:

5 0

4 years ago

Read 2 more answers

Anyone know how to do this? If so PLZ HELP ASAP

pickupchik [31]

Answer:

20

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

Let X represent the amount of gasoline (gallons) purchased by a randomly selected customer at a gas station. Suppose that the me

Alexus [3.1K]

Answer:

a) 18.94% probability that the sample mean amount purchased is at least 12 gallons

b) 81.06% probability that the total amount of gasoline purchased is at most 600 gallons.

c) The approximate value of the 95th percentile for the total amount purchased by 50 randomly selected customers is 621.5 gallons.

Step-by-step explanation:

To solve this question, we use the normal probability distribution and the central limit theorem.

Normal probability distribution

Problems of normally distributed samples are solved using 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.

For sums, we can apply the theorem, with mean $\mu$ and standard deviation $s = \sqrt{n}*\sigma$

In this problem, we have that:

$\mu = 11.5, \sigma = 4$

a. In a sample of 50 randomly selected customers, what is the approximate probability that the sample mean amount purchased is at least 12 gallons?

Here we have $n = 50, s = \frac{4}{\sqrt{50}} = 0.5657$

This probability is 1 subtracted by the pvalue of Z when X = 12.

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

By the Central Limit theorem

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

$Z = \frac{12 - 11.5}{0.5657}$

$Z = 0.88$

$Z = 0.88$ has a pvalue of 0.8106.

1 - 0.8106 = 0.1894

18.94% probability that the sample mean amount purchased is at least 12 gallons

b. In a sample of 50 randomly selected customers, what is the approximate probability that the total amount of gasoline purchased is at most 600 gallons.

For sums, so $mu = 50*11.5 = 575, s = \sqrt{50}*4 = 28.28$