All categories

3 years ago

30x(x-3) multiply please

2 answers:

6 0

You distribute the 30x to the equation in parenthesis

So basically you are doing (30x*x)+(30x*-3)
So you get 30x^2-90x

Hope this helps!

olga2289 [7]3 years ago

3 0

30x(x-3)
lets substitute x for 1
30 * 1(1 - 3)
1 - 3 = 2
30 * 1 = 30
30 * 2 = 60
I hope I did it correctly.

You might be interested in

Pythagorean theorum

tester [92]

A^2+b^2=c^2
Plug in the three numbers into the formula. I hope this helps

3 0

3 years ago

Suppose we are interested in analyzing the weights of NFL players. We know that on average, NFL players weigh 247 pounds with a

Diano4ka-milaya [45]

Answer:

a) The standard error would be of 8.58 pounds.

b) The margin of error is 14.11 pounds.

c) The 90% confidence interval for the population mean is between 232.89 pounds and 261.11 pounds

Step-by-step explanation:

a.What is the standard error?

The standard error is

$s = \frac{\sigma}{\sqrt{n}}$

In which $\sigma$ is the standard deviation of the population and n is the size of the sample. So

$s = \frac{47}{\sqrt{30}} = 8.58$

The standard error would be of 8.58 pounds.

b.What is the margin of error at 90% confidence?

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1-0.9}{2} = 0.05$

Now, we have to find z in the Ztable as such z has a pvalue of $1-\alpha$ .

So it is z with a pvalue of $1-0.05 = 0.95$ , so $z = 1.645$

Now, find the margin of error M as such

$M = z*s = 1.645*8.58 = 14.11$

The margin of error is 14.11 pounds.

c. Using my sample of 30, what would be the 90% confidence interval for the population mean?

Lower bound: Sample mean subtracted by the margin of error.

247 - 14.11 = 232.89 pounds

Upper bound

247 + 14.11 = 261.11 pounds

The 90% confidence interval for the population mean is between 232.89 pounds and 261.11 pounds

4 0

3 years ago

(Look at picture above) Find the volume of the cone. Round your answer to the nearest tenth. 9 yd 7 yd The volume of the cone is

nata0808 [166]

Answer:

V = 115.5 cubic yards

Step-by-step explanation:

V (cone) = 1/3πr²h

just substitute given values to get:

r = 7/2 or 3.5

h = 9

V = π(3.5²)(9)/3

V = 115.5 cubic yards

3 0

2 years ago

8,300 dollars is placed in an account with an annual interest rate of 6.5%. How much will be in the account after 14 years, to t

Inessa [10]

A=8300(1+0.065)^14
A=20,043.46

3 0

3 years ago

What times 3 gives you 1,000

miv72 [106K]

$1,000:3=\frac{1,000}{3}=333\frac{1}{3}\\\\Answer:\boxed{333\frac{1}{3}}\\\\check:\\\\333\frac{1}{3}\times3=\frac{1,000}{3}\times3=1,000$

3 0

3 years ago