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3 years ago

Help I need the answers in 20 minutes

Mathematics

2 answers:

Gelneren [198K]3 years ago

6 0

2. 5 hours

3. $200

4. 9.5 hours. If it has to be whole numbers, 10 hours

Hope that helps!

-scsb17hm

riadik2000 [5.3K]3 years ago

6 0

1) 20
2) 10
3) 100
4) 19

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The point (2.5, 1) is also on the line. What is the vertical change between (2.5, 1) and (5, 2)? What is the horizontal change?

BabaBlast [244]

Answer:

In a general point (x, y) the horizontal component is the x-component, and the vertical component is the y-component.

then if we have the points (a, b) and (c, d)

The vertical distance or change between these points will be the difference between the y-components, and the horizontal distance or change is the difference between the x-components.

Then the vertical change between the points (2.5 , 1) and (5, 2) is:

2 - 1 = 1 unit.

The horizontal change between the points (2.5, 1) and (5, 2) is:

5 - 2.5 = 2.5 units.

4 0

4 years ago

2. In how many ways can 3 different novels, 2 different mathematics books and 5 different chemistry books be arranged on a books

insens350 [35]

The number of ways of the books can be arranged are illustrations of permutations.

When the books are arranged in any order, the number of arrangements is 3628800
When the mathematics book must not be together, the number of arrangements is 2903040
When the novels must be together, and the chemistry books must be together, the number of arrangements is 17280
When the mathematics books must be together, and the novels must not be together, the number of arrangements is 302400

The given parameters are:

$\mathbf{Novels = 3}$

$\mathbf{Mathematics = 2}$

$\mathbf{Chemistry = 5}$

(a) The books in any order

First, we calculate the total number of books

$\mathbf{n = Novels + Mathematics + Chemistry}$

$\mathbf{n = 3 + 2 + 5}$

$\mathbf{n = 10}$

The number of arrangement is n!:

So, we have:

$\mathbf{n! = 10!}$

$\mathbf{n! = 3628800}$

(b) The mathematics book, not together

There are 2 mathematics books.

If the mathematics books, must be together

The number of arrangements is:

$\mathbf{Maths\ together = 2 \times 9!}$

Using the complement rule, we have:

$\mathbf{Maths\ not\ together = Total - Maths\ together}$

This gives

$\mathbf{Maths\ not\ together = 3628800 - 2 \times 9!}$

$\mathbf{Maths\ not\ together = 2903040}$

(c) The novels must be together and the chemistry books, together

We have:

$\mathbf{Novels = 3}$

$\mathbf{Chemistry = 5}$

First, arrange the novels in:

$\mathbf{Novels = 3!\ ways}$

Next, arrange the chemistry books in:

$\mathbf{Chemistry = 5!\ ways}$

Now, the 5 chemistry books will be taken as 1; the novels will also be taken as 1.

Literally, the number of books now is:

$\mathbf{n =Mathematics + 1 + 1}$

$\mathbf{n =2 + 1 + 1}$

$\mathbf{n =4}$

So, the number of arrangements is:

$\mathbf{Arrangements = n! \times 3! \times 5!}$

$\mathbf{Arrangements = 4! \times 3! \times 5!}$

$\mathbf{Arrangements = 17280}$

(d) The mathematics must be together and the chemistry books, not together

We have:

$\mathbf{Mathematics = 2}$

$\mathbf{Novels = 3}$

$\mathbf{Chemistry = 5}$

First, arrange the mathematics in:

$\mathbf{Mathematics = 2!}$

Literally, the number of chemistry and mathematics now is:

$\mathbf{n =Chemistry + 1}$

$\mathbf{n =5 + 1}$

$\mathbf{n =6}$

So, the number of arrangements of these books is:

$\mathbf{Arrangements = n! \times 2!}$

$\mathbf{Arrangements = 6! \times 2!}$

Now, there are 7 spaces between the chemistry and mathematics books.

For the 3 novels not to be together, the number of arrangement is:

$\mathbf{Arrangements = ^7P_3}$

So, the total arrangement is:

$\mathbf{Total = 6! \times 2!\times ^7P_3}$

$\mathbf{Total = 6! \times 2!\times 210}$

$\mathbf{Total = 302400}$

Read more about permutations at:

brainly.com/question/1216161

8 0

3 years ago

A sporting goods store purchased a snowboard and marked it up 25% from the original cost of $120. Then, wanting to make room for

Margaret [11]

The price after the discount was $45.

When the sporting goods store bought the snowboard and marked it up by 25%, the price became:

= Original cost x ( 1 + markup percentage)

= 120 x ( 1 + 25%)

= 120 x 1.25

= $150

The snowboard was then discounted by 70%, the new price becomes:

= Current price x ( 1 - discount rate)

= 150 x ( 1 - 70%)

= 150 x 30%

= $45

In conclusion, the price after the discount was $45.

Find out more at brainly.com/question/1472521.

3 0

2 years ago

Please help me on all of these please and thank you I’m putting all my points for it please

love history [14]

1. 3
2. 4
3. 10
4. 15
5. 50
6. 40

I'm a beginner, and I haven't done this kind of math in a while, but I hope this helps. Have a great day!

- Blue

6 0

3 years ago

Read 2 more answers

PLEASE HELP! If I add five to a mystery number and then multiply the result by two, I get twenty four. Write an equation to solv

dezoksy [38]

Answer:

The mystery number is 7

Step-by-step explanation:

This is a very easy problem.

let the mystery number=x

2(x+5)=24

2x+10=24

2x=24-10

2x=14

x=7

To check the answer,

Add 5 to 7=12, multiply by 2=24

6 0

3 years ago