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
Anika [276]
3 years ago
14

If a get a 50 on a test and have a 90 in a class how much will it bring me down?

Mathematics
1 answer:
Art [367]3 years ago
3 0
Usually test are worth 5-7% of your mark
You might be interested in
X+8=21 I need helpppp
Mrac [35]
You add 13 and 8 it gets 21 so for X its 13
8 0
3 years ago
Read 2 more answers
At a large Midwestern university, a simple random sample of 100 entering freshmen in 1993 found that 20 of the sampled freshmen
guajiro [1.7K]

Answer:

The 90% confidence interval for the difference of proportions is (0.01775,0.18225).

Step-by-step explanation:

Before building the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.

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.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean \mu = p and standard deviation s = \sqrt{\frac{p(1-p)}{n}}

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

p1 -> 1993

20 out of 100, so:

p_1 = \frac{20}{100} = 0.2

s_1 = \sqrt{\frac{0.2*0.8}{100}} = 0.04

p2 -> 1997

10 out of 100, so:

p_2 = \frac{10}{100} = 0.1

s_2 = \sqrt{\frac{0.1*0.9}{100}} = 0.03

Distribution of p1 – p2:

p = p_1 - p_2 = 0.2 - 0.1 = 0.1

s = \sqrt{s_1^2+s_2^2} = \sqrt{0.04^2 + 0.03^2} = 0.05

Confidence interval:

p \pm zs

In which

z is the z-score that has a p-value of 1 - \frac{\alpha}{2}.

90% confidence level

So \alpha = 0.1, z is the value of Z that has a p-value of 1 - \frac{0.1}{2} = 0.95, so Z = 1.645.  

The lower bound of the interval is:

p - zs = 0.1 - 1.645*0.05 = 0.01775


The upper bound of the interval is:

p + zs = 0.1 + 1.645*0.05 = 0.18225


The 90% confidence interval for the difference of proportions is (0.01775,0.18225).

6 0
3 years ago
Please help me with this question ​
Tema [17]
............................

8 0
3 years ago
In a certain town there were 235 robberies last year. This year the number of robberies has gone down 33%. How many robberies we
HACTEHA [7]

Answer:

157 is the answer

Step-by-step explanation:

If you go on google and type 235- 33% you get 157.45 and to the nearest whole number is 157 hope that helped.

6 0
3 years ago
Solve the inequality <br><br> 4b
Mnenie [13.5K]
Could you maybe provide us with a better explantion or picture?
4 0
3 years ago
Other questions:
  • Nick had 14 jelly beans in a bag. His mother put a handful of jelly beans in the bag. When Nick counts his jelly beans, he disco
    5·2 answers
  • Fill in the blank to make the following a true statement.
    12·1 answer
  • Number 9 and 10. Say which one you r doing plzzz
    11·1 answer
  • A group of friends are going to see a movie. The admission cost is $8 per person. The table below represents the number of frien
    14·2 answers
  • TIMED TEST PLEASE HELP ME!!!!
    11·1 answer
  • John withdrew 1/4 of his savings to use as deposit on a new phone.He had 164.00 in his savings account.How did John withdrew for
    14·1 answer
  • Question below, please answer
    7·1 answer
  • Y is directly proportional to x. when y=30, x=6. A) work out an equation connecting y and x. B) work out what the value of y whe
    13·1 answer
  • Section 5.2 Problem 19:
    14·1 answer
  • Michael drove from home to work at an average speed of 45 mph. His return trip home took 45 minutes longer because he could only
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!