1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Dahasolnce [82]
3 years ago
7

Simplify x + 4 - 5x - 2

Mathematics
2 answers:
allochka39001 [22]3 years ago
5 0

The simplest form would be -4x + 2

Masja [62]3 years ago
5 0

Answer: -4x +2 yes it's simplified

You might be interested in
13. The figure below shows three identical squares ABCD, CEFG and CJIH
Maru [420]

Step-by-step explanation:

DCE²+GCH²+X²=180°

40²+27²+X²=180°

x²=2329-180°

x=√2149

x=49//

7 0
3 years ago
The time for a visitor to read health instructions on a Web site is approximately normally distributed with a mean of 10 minutes
klio [65]

Answer:

a) The mean is 10 and the variance is 0.0625.

b) 0.6826 = 68.26% probability that the mean time of the visitors is within 15 seconds of 10 minutes.

c) 10.58 minutes.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean \mu and standard deviation \sigma, the z-score 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 p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes 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.

Normally distributed with a mean of 10 minutes and a standard deviation of 2 minutes.

This means that \mu = 10, \sigma = 2

Suppose 64 visitors independently view the site.

This means that n = 64,  = \frac{2}{\sqrt{64}} = 0.25

a. The expected value and the variance of the mean time of the visitors.

Using the Central Limit Theorem, mean of 10 and variance of (0.25)^2 = 0.0625.

b. The probability that the mean time of the visitors is within 15 seconds of 10 minutes.

15 seconds = 15/60 = 0.25 minutes, so between 9.75 and 10.25 seconds, which is the p-value of Z when X = 10.25 subtracted by the p-value of Z when X = 9.75.

X = 10.25

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

By the Central Limit Theorem

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

Z = \frac{10.25 - 10}{0.25}

Z = 1

Z = 1 has a p-value of 0.8413.

X = 9.75

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

Z = \frac{9.75 - 10}{0.25}

Z = -1

Z = -1 has a p-value of 0.1587.

0.8413 - 0.1587 = 0.6826.

0.6826 = 68.26% probability that the mean time of the visitors is within 15 seconds of 10 minutes.

c. The value exceeded by the mean time of the visitors with probability 0.01.

The 100 - 1 = 99th percentile, which is X when Z has a p-value of 0.99, so X when Z = 2.327.

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

2.327 = \frac{X - 10}{0.25}

X - 10 = 2.327*0.25

X = 10.58

So 10.58 minutes.

6 0
3 years ago
You and your brother are reading the same novel. You want to get ahead of him in the book, so you decide to read 30 minutes long
Sholpan [36]

Answer: its 45 if i read it right.

Step-by-step explanation:

8 0
3 years ago
the national flag of scotland has a white diagonal on a blue backround Tracy is sewing a scottish flag she knows that the length
dybincka [34]

Answer:

12 feet

Step-by-step explanation:

By Pythagoras theorem, a²+b²=c², where c represents the diagonal and a and b represents the other sides of a right angled triangle

As a flag is a rectangle, the two triangles cut would be  right angled triangles

Therefore, a²+9²=15²

a²+81=225

a²=144

a=√144

a=12 feet

7 0
3 years ago
A certain dishwasher uses 29 kilowatts of energy per hour.if the dishwasher was used 156 hours last year how many kilowatts of e
hram777 [196]
156 x 29 = 4524 kilowatts of energy
6 0
3 years ago
Other questions:
  • Which of the following statements is NOT true regarding an expression written in scientific notation in teh form of a x 10^n?
    11·2 answers
  • HELP ASAP!!! you have 12 pennies in your pocket. Of those pennies, 3 are Canadian. suppose you pick a penny out of your pocket a
    12·1 answer
  • Write 0.751 in words
    6·2 answers
  • Create a reciprocal function that has been translated left 2 units and up 4 units​
    5·1 answer
  • Layla bought a pencil for $1.25, a pen for $2.25, and three erasers for $0.45 each. She gave the cashier $10 for the items. How
    7·2 answers
  • Select the expressions that are equivalent to 12n - 8 sellect all that apply .
    14·1 answer
  • Is 25 meters longer then 35 yards
    13·2 answers
  • Solve this to be my best friend
    14·1 answer
  • Need help with this quick plz??
    14·1 answer
  • What is 2592x340?<br> answer
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!