Which one is it a b or c or d . ?

Bobby wants to go on a school trip that will cost him $250. He comes up with an equation that represents how much he needs to sa

monitta

Yes, Bobby will have enough money if he saves for 9 weeks. You can find this through either substituting w for 9 in the equation, or solving the equation itself.

Substituting:

$25(9)+30$
Substitute w for 9.

$225+30$
Simplify.

$225+30=255$
Solve.

255 is greater than 250, so yes, he will have enough money saved.

Solving the equation:

$25w+30=250$
Original Equation

$25w=220$
Subtract 30 from both sides.

$w=8.8$
Divide both sides by 25.

The number of weeks he needs is 8.8. When rounding it up, you get 9.

4 0

3 years ago

Simplify 12(6)-7(2)+(6-3)

Ber [7]

Step-by-step explanation:

12(6) - 7(2) + (6-3)

48 - 14 + 2

36

5 0

3 years ago

Read 2 more answers

You are given the sample mean and the population standard deviation. Use this information to construct the 90% and 95% confide

FrozenT [24]

Question:

You are given the sample mean and the population standard deviation. Use this information to construct the 90% and 95% confidence intervals for the population mean. Interpret the results and compare the widths of the confidence intervals. If convenient, use technology to construct the confidence intervals. A random sample of 45 home theater systems has a mean price of $114.00. Assume the population standard deviation is $15.30. Construct a 90% confidence interval for the population mean.

Answer:

At the 90% confidence level, confidence interval = 110.2484 < μ < 117.7516

At the 95% confidence level, confidence interval = 109.53 < μ < 118.48

The 95% confidence interval is wider

Step-by-step explanation:

Here, we have

Sample size, n = 45

Sample mean, $\bar x$ = $114.00

Population standard deviation, σ = $15.30

The formula for Confidence Interval, CI is given by the following relation;

$CI=\bar{x}\pm z\frac{\sigma}{\sqrt{n}}$

Where, z is found for the 90% confidence level as ±1.645

Plugging in the values, we have;

$CI=114\pm 1.645 \times \frac{15.3}{\sqrt{45}}$

or CI: 110.2484 < μ < 117.7516

At 95% confidence level, we have our z value given as z = ±1.96

From which we have $CI=114\pm 1.96 \times \frac{15.3}{\sqrt{45}}$

Hence CI: 109.53 < μ < 118.48

To find the wider interval, we subtract their minimum from the maximum as follows;

90% Confidence level: 117.7516 - 110.2484 = 7.5

95% Confidence level: 118.47503 - 109.5297 = 8.94

Therefore, the 95% confidence interval is wider.

8 0

3 years ago

Read 2 more answers

The shape above has the following

Ira Lisetskai [31]

It’s A 44-1) and if not then it’s b

8 0

2 years ago

What is the solution to the system of equations graphed below?<br><br> y=x+3<br> y=3x+1

Mademuasel [1]

Answer:

(1, 4)

Step-by-step explanation:

y=x+3

y=3x+1

y=x+3

x+3=3x+1

x=3x-2

-2x=-2

x=1

y=1+3

y=4

8 0

3 years ago