Can someone please help me with this? ^^"

Find the inner product for (-4,9,8) . (3,2,-2) and state whether the vectors are perpendicular.

drek231 [11]

Answer:

-10; no

Step-by-step explanation:

<h2>-4*3 + 9*2 + 8*-2 = -10</h2><h2></h2><h2>-10 does not equal 0 so it is not perpendicular</h2>

6 0

3 years ago

Connecticut families were asked how much they spent weekly on groceries. Using the following data, construct and interpret a 95%

Amanda [17]

Answer:

The 95% confidence interval for the population mean amount spent on groceries by Connecticut families is ($73.20, $280.21).

Step-by-step explanation:

The data for the amount of money spent weekly on groceries is as follows:

S = {210, 23, 350, 112, 27, 175, 275, 50, 95, 450}

n = 10

Compute the sample mean and sample standard deviation:

$\bar x =\frac{1}{n}\cdot\sum X=\frac{ 1767 }{ 10 }= 176.7$

$s= \sqrt{ \frac{ \sum{\left(x_i - \overline{x}\right)^2 }}{n-1} } = \sqrt{ \frac{ 188448.1 }{ 10 - 1} } \approx 144.702$

It is assumed that the data come from a normal distribution.

Since the population standard deviation is not known, use a t confidence interval.

The critical value of t for 95% confidence level and degrees of freedom = n - 1 = 10 - 1 = 9 is:

$t_{\alpha/2, (n-1)}=t_{0.05/2, (10-1)}=t_{0.025, 9}=2.262$

*Use a t-table.

Compute the 95% confidence interval for the population mean amount spent on groceries by Connecticut families as follows:

$CI=\bar x\pm t_{\alpha/2, (n-1)}\cdot\ \frac{s}{\sqrt{n}}$

$=176.7\pm 2.262\cdot\ \frac{144.702}{\sqrt{10}}\\\\=176.7\pm 103.5064\\\\=(73.1936, 280.2064)\\\\\approx (73.20, 280.21)$

Thus, the 95% confidence interval for the population mean amount spent on groceries by Connecticut families is ($73.20, $280.21).

7 0

3 years ago

The ratio of boys to girls at a movie is 3:4 . If there are 16 girls , how many boys are at the movie?

Annette [7]

Answer:

12 boys

Step-by-step explanation:

Set up a proportion: $\frac{3}{4} = \frac{x}{16}$
Cross multiply, then divide: 3 × 16 = 48, 48 ÷ 4 = 12

I hope this helps!

8 0

3 years ago

Read 2 more answers

How to solve 19= -37 + 8x

lions [1.4K]

Answer:

19 = -37 + 8x

-8x= -37 -19

-8x = -56

x= 7

4 0

2 years ago

16x+14y=8 -63x-14y=133

artcher [175]

Answer:

(-3, 4)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Algebra I

Solving systems of equations using substitution/elimination
Solving systems of equations by graphing

Step-by-step explanation:

Step 1: Define Systems

16x + 14y = 8

-63x - 14y = 133

Step 2: Solve for x

Elimination

Combine 2 equations: -47x = 141
Divide -47 on both sides: x = -3

Step 3: Solve for y

Define original equation: 16x + 14y = 8
Substitute in x: 16(-3) + 14y = 8
Evaluate multiplication: -48 + 14y = 8
Add 48 on both sides: 14y = 56
Divide 14 on both sides: y = 4

Step 4: Graph Systems

Check the solution set.

4 0

2 years ago