You can walk 1.5 miles in a half hour. What is your average speed?

To which set of numbers does -1/4 belong to?

inna [77]

Real numbers and rational numbers

7 0

3 years ago

5x +7 y=-17<br> 4x – 3y = -5<br> Substitute.

Bond [772]

Answer:

(x,y) = (-2, -1)

Step-by-step explanation:

We start off by substituting the value of "x".

5x+7y=-17

x=- $\frac{5}{4} + \frac{3}{4}y$

We then solve 5 $5(-\frac{5}{4}+\frac{3}{4}y ) +7y= -17$

y=-1 *Substitute the value of "y"

x= - $-\frac{5}{4}+\frac{3}{4}x(-1)$

x=-2

$\left \{ {{-17=-17} \atop {-5=-5}} \right.$ This works.

5 0

3 years ago

Annie needs $30 to buy a coat she has saved $12 and plans to work as a baby siter to earn $6 per hour which inequality shows the

tekilochka [14]

Answer:

The answer would be B. 12 + 6n is greater than or equal to 30, so n is less than or equal to 3.

explanation:

I'm bad with explaining things, but I'll try my best to explain why this is the right answer.

12 + 6n ≥ 30, so n ≤ 3

let's start with the 12 at the beginning of the inequality, Annie already has $12, so the 12 in the inequality shows the amount of money she already has being added to the $6 per hour of babysitting she needs to do (n).

Now for the + 6n, the plus is there to show that the $12 Annie already has is being added to the 6n. The 6n then represents the $6 Annie makes each hour and the n represents how many hours she needs to babysit in order to get $30. The 6 is being multiplied by the amount of hours she needs to babysit to show how much money Annie would make. Then you add on the $12 she already has.

Annie then needs at least $30, but if she makes more than $30 then she will simply have more money than needed, therefore you use the greater than or equal to sign to show that she can have more money than just $30 after working.

I hope this helps, and sorry if my explanation is hard to understand lol.

6 0

3 years ago

Kendra found this relationship between the quantities in the table.

slava [35]

Answer:

Kendra should have multiplied the x-values by 75 to get the y-values

Step-by-step explanation:

Given

Table

X|| Y

1 || 75

2 || 150

3 || 225

4 || 300

5 || 375

Given that Kendra multiply x by 7.5 to get y

The relationship of x and y can be calculated as thus;

y = rx

Where y and x are the values at the y and x column respectively and r is the constant of proportionality

When y = 75, x = 1.

Plug in these values in the above formula

y = rx becomes

75 = r * 1

75 = r

r = 75

When y = 150, x = 2

150 = r * 2

Multiply both sides by ½

150 * ½ = r * 2 * ½

75 = r

r = 75

When y = 225, x = 3

225 = r * 3

Multiply both sides by ⅓

225 * ⅓ = r * 3 * ⅓

75 = r

r = 75

Notice that r remains 75 and the difference between y values is 75

If you apply these formula on when y = 300 or 375 and when x = 4 or 5, the constant of proportionality will remain The value of 75.

Hence, Kendra mistake is that; Kendra should have multiplied the x-values by 75 to get the y-values

6 0

3 years ago

Read 2 more answers

Determine whether there is a difference between the two data sets that is not apparent from a comparison of the measures of cent

Iteru [2.4K]

Answer:

It seems the question is incomplete as the two data sets implied from the question are not visible.

However, two data sets having identical measures of center have a difference.

Step-by-step explanation:

Let's consider these two data sets:

2, 2, 3, 5, 6, 6 and 1, 1, 1, 1, 1, 19

Both were contrived.

The most reliable among the measures of center is the mean. The mean of each is calculated by summing the data and dividing by the number of elements. In both sets, the mean is 4.

The data in the first set seem to be concentrated around the mean indeed. But for the second data set, one of them, 19, is obviously very far from the others and the mean. We need another measure to describe this: standard deviation.

Its formula is:

$\rho=\sqrt{\dfrac{\sum (x-\overline{x})^2}{n}}$

$x$ represents each data, $\overline{x}$ is the mean and $n$ is the number of items. $x-\overline{x}$ is the deviation from the mean of each data item.

For the first data set, $\rho=\sqrt{6}=2.45$

For the second data set,

$\rho=\sqrt{45}=6.71$

The low value of $\rho$ for the first set indicates that the items are all closer to the mean than for the second set.

Variance is the square of the standard deviation. It could also be used.

7 0

3 years ago