Help me answer this question please

How do you write and solve a system of equations from a word problem?

Sergeu [11.5K]

See this question for an example.
brainly.com/question/8829608

Step 1. Read and understand the description of the problem.
Step 2. Identify what the problem is asking you do do.
Step 3. Identify the given information and the given relationships.
Step 4. Use your knowledge of the relationships associated with the parts of the problem, along with the result of Step 3, to write equations relating the given information and the information you are asked to find.
Step 5. Solve those equations using the rules of algebra.
Step 6. Check to make sure your solution satisfies all of the problem conditions and requests.

_____
With respect to the example problem above, you are expected to know how the total bill is calculated when you make a purchase. A lot of people act like they don't understand how this works, even though they have been shopping many times. This is what is meant by Step 4--use your knowledge.

7 0

3 years ago

How would adding a 0 to this data affect the mean and Median game scores

Ede4ka [16]

Answer:

Basically adding 0 doesn't change the mean but it does change the median

Step-by-step explanation:

(Median before adding 0)=125

(Median before adding 0)=120

5 0

4 years ago

Pls help meeee (8/n^5)^6

marishachu [46]

8^6/n^30=262144/n^30

7 0

3 years ago

1. Rule: Each succeeding term is obtained by multiplying the two previous ones. Write the next five terms of the sequence. 1, 3,

kotegsom [21]

5, 7, 9, 11, 13 add 2

5 0

4 years ago

Pay your bills: In a large sample of customer accounts, a utility company determined that the average number of days between whe

blagie [28]

Answer:

(26.32; 57.68)

See explanation below.

Step-by-step explanation:

Assuming the following question:

Pay your bills:

In a large sample of customer accounts, a utility company determined that the average number of days between when a bill was sent out and when the payment was made is 42 with a standard deviation of 8 days. Assume the data to be approximately bell-shaped.

Between what two values will approximately 95% of the numbers of days be?

Solution to the problem

Previous concepts

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".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Let X the random variable that represent the average number of days between when a bill was sent out and when the payment of a population, and for this case we know the distribution for X is given by:

$X \sim N(42,8)$

Where $\mu=42$ and $\sigma=8$

For this part we want to find a value a, such that we satisfy this condition:

$P(X>a)=0.975$ (a)

$P(X$ (b)

Both conditions are equivalent on this case. We can use the z score in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.025 of the area on the left and 0.975 of the area on the right it's z=-1.96. On this case P(Z<-1.96)=0.025 and P(z>-1.96)=0.975

If we use condition (b) from previous we have this:

$P(X$

$P(z$

But we know which value of z satisfy the previous equation so then we can do this:

$z=-1.96$

And if we solve for a we got

$a=42 -1.96*8=26.32$

So the value of height that separates the bottom 2.5% of data from the top 97.5% is 26.32.

For the other value since the distirbution is symmetric the other value that accumulates 0.975 of the area on the left and 0.025 on the right is z=1.96 and similarly:

$z=1.96$

And if we solve for a we got

$a=42 +1.96*8=57.68$

So the answer for this case would be (26.32; 57.68)

3 0

3 years ago