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3 years ago

Can you help plz and explain

Mathematics

1 answer:

Harrizon [31]3 years ago

6 0

Answer:

is x = 2

Step-by-step explanation:

given in the image hopefully it helps if you need any more explanation let me know :)

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A ski rental store rents a pair of skis for $44 a day and a snowboard for $58 a day. Yesterday, the store made $2,232 on ski and

Katen [24]

First, let the number of skis rented by x and the number of snowboards rented by y. We can then assemble the first equation from the amount of money made from the rentals.

44x + 58y = 2232

The second equation can come from the fact that 9 more skis were rented than snowboards.

y = x - 9

Therefore our system is:

44x + 58y = 2232

y = x - 9

3 0

4 years ago

Help me please

Andreyy89

Answers:

Part (a) upper bound for area = 4527.7056 square cm
Part (b) lower bound for perimeter = 278 cm

======================================================

Explanation:

Part (a)

The horizontal portion is shown to be 87.3 cm long. This is the result <em>after</em> rounding has occurred. Specifically, rounding to one decimal place (tenths). The question is: What could the number have been <em>before</em> rounding?

You have to think in reverse of the usual rounding process.

The values 87.25, 87.26, 8.27, ... 8.33, 87.34 all round to 87.3 when we round to one decimal digit. Note the hundredths digit is increasing by 1 each time. We can see that 87.34 is the largest possible value for the horizontal piece. After that, 87.35 will round to 87.4 which is just out of reach.

Through similar logic/reasoning, the vertical side can be at most 51.84 cm.

The area of the rectangle could be 87.34*51.84 = 4527.7056 which is the upper bound for the area. This is the largest possible area, given the values in the diagram, since we made each value as large as possible.

In short, 4527.7056 square cm is the max area.

-----------------------------------

Part (b)

We use the idea of part (a), but we'll use the smallest possible values this time.

So we go with 87.25 for the horizontal portion and 51.75 for the vertical portion.

Compute the perimeter with these smallest dimensions.

P = 2*(length + width)

P = 2*(87.25 + 51.75)

P = 278

The smallest perimeter possible is 278 cm which is the lower bound of the perimeter. This is guaranteed to be the smallest perimeter possible because we made the sides as small as possible, while staying in the restrictions as discussed in the previous section.

7 0

3 years ago

A researcher reports the following confidence interval for a comparison of the difference between two groups: 95% CI −12.0 [−30.

Lapatulllka [165]

Answer:

Decision: Support the null hypothesis.

Sample mean: -12

Step-by-step explanation:

Hello!

When deciding with a Confidence interval you have to keep in mind that the following conditions are met:

The hypothesis and the interval are made for the same parameter.
The hypothesis should be two-tailed.
The interval and the test have to have complementary confidence and signification levels. This means that if the interval is made with 1 - α= 0.95 the hypothesis test should be made with α= 0.05.

H₀: μ₁ - μ₂= 0

H₁: μ₁ - μ₂≠ 0

α: 0.05

If the interval contains the cero, it means that there is no difference between the means, so you support the null hypothesis.

If the interval doesn't contain the cero, there is a difference between the two means, so you reject the null hypothesis.

The intervals to estimate the population mean have the following structure:

Estimator ± Margin of error

This means that the sample mean (point estimate of the population mean) is in the middle of the calculated interval. To know it's the value you have to do a simple calculation:

sample mean: $\frac{Upper bound + Lower bound}{2}$

sample mean: $\frac{6 + (-30)}{2}$

sample mean: -12

I hope it helps!

7 0

4 years ago

Grace has 16 jellybeans in her pocket. She has 8 red ones, 4 green ones, and 4 blue ones. What is the minimum number of jellybea

Fofino [41]

She must take all of the jellybeans. If she only takes out a certain number of jellybeans then there could be a probability that all colors won't come. By taking all of them out she could be sure.

3 0

3 years ago

The current population of china is one, 1,244,130, 000 estimate the population in scientific notation

Yanka [14]

Answer: 1.24413 x $10^{9}$

Step-by-step explanation:

8 0

4 years ago

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