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
grin007 [14]
2 years ago
14

Julio says, "If you subtract 19 from my number and multiply the difference by - 7, the result is - 28." What is Julio's number?

Mathematics
1 answer:
ra1l [238]2 years ago
4 0

Answer:

23

Step-by-step explanation:

Basically I did it backwards & opposites:

-28 divided by -7 = 4

4 + 19 = 23

I checked btw and it worked.

You might be interested in
From 19 measurements of a pressure controller, the mean operating pressure is 4.97 kPa with a standard deviation of 0.0461 kPa.
Semenov [28]

Answer:

4.97-2.10\frac{0.0461}{\sqrt{19}}=4.95    

4.97+2.10\frac{0.0461}{\sqrt{19}}=4.99    

So on this case the 95% confidence interval would be given by (4.95;4.99)  

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

\bar X =4.97 represent the sample mean

\mu population mean (variable of interest)

s=0.0461 represent the sample standard deviation

n=19 represent the sample size  

Confidence interval

The confidence interval for the mean is given by the following formula:

\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}   (1)

In order to calculate the critical value t_{\alpha/2} we need to find first the degrees of freedom, given by:

df=n-1=19-1=18

Since the Confidence is 0.95 or 95%, the value of \alpha=0.05 and \alpha/2 =0.025, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,18)".And we see that t_{\alpha/2}=2.10

Now we have everything in order to replace into formula (1):

4.97-2.10\frac{0.0461}{\sqrt{19}}=4.95    

4.97+2.10\frac{0.0461}{\sqrt{19}}=4.99    

So on this case the 95% confidence interval would be given by (4.95;4.99)    

5 0
3 years ago
How can you determine the number of solutions for an equation
ryzh [129]
The way to determine the number of solutions is to complete the problem in multiple different ways.
5 0
3 years ago
80% of what number is 15
joja [24]
X time 0.8 (or 80 percent)= 15
so 15/0.8=X
18.75
4 0
3 years ago
-2x^4 +50x^2+0x-3/x-5
Gemiola [76]
1) "x2" was replaced by "x^2". 1 more similar replacement(s).
Raising zero to a power is not allowed
3 0
3 years ago
Lines l and m are parallel
soldi70 [24.7K]

Answer:

  • m∠ABC = 15°

Step-by-step explanation:

<u>Given</u>

  • m∠ABC = x°
  • m∠BCD = 25°
  • m∠CDE = 55°
  • m∠DEF = 3x°

Add two more parallel lines passing through points C and D.

Consider alternate interior angles formed by the four parallel lines.

<u>The angles between the two middle lines are equal to:</u>

  • m∠BCD - m∠ABC  = m∠CDE - m∠DEF

<u>Substitute values and solve for x:</u>

  • 25 - x = 55 - 3x
  • 3x - x = 55 - 25
  • 2x = 30
  • x = 15

m∠ABC = 15°

4 0
3 years ago
Other questions:
  • Need urgent help!?
    7·2 answers
  • HALP<br> PLLLLLLZZZZZZZ<br> ILL GIVE U BRAINLIEST!!
    12·1 answer
  • Suppose △ITH≅△APG.<br><br> Which congruency statement is true?
    8·2 answers
  • Help with my math please
    13·1 answer
  • Use the Distributive Property to expand the expression -3(6.3x + 1.5y)
    6·1 answer
  • 1 + hk + j use h=-5, j = -6, and k = 6<br> Help me
    15·1 answer
  • Two sides and the non-included
    13·2 answers
  • Help please been struggling
    5·1 answer
  • Jacob has 17 yards of fabric. He uses 1 third of it to make a cape. How many yards of fabric does Jacob use for the cape?
    12·2 answers
  • Anyone know how to do this?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!