Ask question

Ask question

All categories

2 years ago

12

Mandy bought 5 computer games and a carrying case for a total of $155. The carrying case cost $15. Each computer game cost the s

ame amount. What is the cost of each computer game?

1 answer:

Elina [12.6K]2 years ago

8 0

Set up an algebraic equation to find the cost of each game. 5x+15=155. x is the cost of each game multiplied by 5(total amount of games). 15 is the cost or the carrier. 155 is the total cost. Now you solve: 5x+15=155, 5x=140, x=28. The cost of each game is $28. Check: 5 (28)+15=155

You might be interested in

Caleb started with 50 bacteria for his science experiment and they doubled in one day. Jenna also started with 50 bacteria for h

MrRa [10]

Answer: B

Step-by-step explanation:

The second power basically means that you multiply the number by itself that many times depending on the power, and since it's 50^2, the answer is Caleb - 100 | Jenna - 2,500. (Tip: Just multiply 50 x 50)

4 0

2 years ago

Nancy's 50-meter freestyle swim time was 28.004 seconds. Betty’s 50-meter freestyle swim time was 27.949 seconds. What was the d

loris [4]

The difference between the 2 times would be .055 seconds...

6 0

2 years ago

Read 2 more answers

Among a simple random sample of 331 American adults who do not have a four-year college degree and are not currently enrolled in

Hitman42 [59]

Answer:

(1) Therefore, a 90% confidence interval for the proportion of Americans who decide to not go to college because they cannot afford it is [0.4348, 0.5252].

(2) We can be 90% confident that the proportion of Americans who choose not to go to college because they cannot afford it is contained within our confidence interval

(3) A survey should include at least 3002 people if we wanted the margin of error for the 90% confidence level to be about 1.5%.

Step-by-step explanation:

We are given that a simple random sample of 331 American adults who do not have a four-year college degree and are not currently enrolled in school, 48% said they decided not to go to college because they could not afford school.

Firstly, the pivotal quantity for finding the confidence interval for the population proportion is given by;

P.Q. = $\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of Americans who decide to not go to college = 48%

n = sample of American adults = 331

p = population proportion of Americans who decide to not go to

college because they cannot afford it

<em>Here for constructing a 90% confidence interval we have used a One-sample z-test for proportions.</em>

<em />

<u>So, 90% confidence interval for the population proportion, p is ;</u>

P(-1.645 < N(0,1) < 1.645) = 0.90 {As the critical value of z at 5% level

of significance are -1.645 & 1.645}

P(-1.645 < $\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ < 1.645) = 0.90

P( $-1.645 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ < $\hat p-p$ < $1.645 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ) = 0.90

P( $\hat p-1.645 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ < p < $\hat p+1.645 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ) = 0.90

<u>90% confidence interval for p</u> = [ $\hat p-1.645 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ , $\hat p+1.645 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ]

= [ $0.48 -1.96 \times {\sqrt{\frac{0.48(1-0.48)}{331} } }$ , $0.48 +1.96 \times {\sqrt{\frac{0.48(1-0.48)}{331} } }$ ]

= [0.4348, 0.5252]

(1) Therefore, a 90% confidence interval for the proportion of Americans who decide to not go to college because they cannot afford it is [0.4348, 0.5252].

(2) The interpretation of the above confidence interval is that we can be 90% confident that the proportion of Americans who choose not to go to college because they cannot afford it is contained within our confidence interval.

3) Now, it is given that we wanted the margin of error for the 90% confidence level to be about 1.5%.

So, the margin of error = $Z_(_\frac{\alpha}{2}_) \times \sqrt{\frac{\hat p(1-\hat p)}{n} }$

$0.015 = 1.645 \times \sqrt{\frac{0.48(1-0.48)}{n} }$

$\sqrt{n} = \frac{1.645 \times \sqrt{0.48 \times 0.52} }{0.015}$

$\sqrt{n}$ = 54.79

n = $54.79^{2}$

n = 3001.88 ≈ 3002

Hence, a survey should include at least 3002 people if we wanted the margin of error for the 90% confidence level to be about 1.5%.

5 0

2 years ago

To control pollination, pollen-producing flowers are often removed from the top of corn in a process called detasseling. The hou

____ [38]

Answer: <u>Last option</u>

$Z_ {13} = 0.5,\ Z_ {17} = 2.5$

Step-by-step explanation:

The z-scores give us information about how many standard deviations from the mean the data are. This difference can be negative, if the data are n deviations to the left of the mean, or it can be positive if the data are n deviations to the right of the mean.

To calculate the Z scores, we calculate the difference between the value of the data and the mean and then divide this difference by the standard deviation.

so

$Z = \frac{x- \mu}{\sigma}$ .

Where x is the value of the data, μ is the mean and σ is the standard deviation

In this case :

μ = 12 $/h

$\sigma$ = 2 $/h

We need to calculate the Z-scores for $x = 17$ and $x = 13$

Then for $x = 17$ :

$Z_{17} = \frac{17-12}{2}$ .

$Z_{17} = 2.5$

Then for $x = 13$ :

$Z_{13} = \frac{13-12}{2}$ .

$Z_{13} = 0.5$

Therefore the answer is:

$Z_ {13} = 0.5,\ Z_ {17} = 2.5$

8 0

2 years ago

Read 2 more answers

Which is the graph of the linear inequality 2x – 3y < 12? On a coordinate plane, a solid straight line has a positive slope a

RoseWind [281]

Answer:

A dashed straight line has a positive slope and goes through (0, negative 4) and (3, negative 2). Everything to the right of the line is shaded.

Step-by-step explanation:

To graph the solution set of the inequality 2x - 3y < 12, first plot the dashed line 2x - 3y = 12 (dashed because the inequality has sign < without notion "or equal to"). This line passes through the points (0,-4) and (3,-2) (their coordinates satisfy the equation of the line). this line has positive slope because

$3y=2x-12\\ \\y=\dfrac{2}{3}x-4$

and the slope of the line is 2/3.

Now, identify where the origin is (in the region or outside the region). Substitute (0,0) into the inequality:

$2\cdot 0-3\cdot 0=0$

This means coordinates of the origin satisfy the inequality, so origin belongs to the shaded region. Thus, shade that part which contains origin.

6 0

2 years ago

Read 2 more answers