1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Studentka2010 [4]
3 years ago
15

There are 420 books on a bookcase with 7 shelves. Each shelf has the same number of books. How many books are on 4 shelves? 28 6

0 120 240 ...
Mathematics
1 answer:
Ghella [55]3 years ago
3 0
If we have 420 books for every 7 shelves and are looking for how many books are on 4 shelves, we need to set up fractional proportions.

We have 7 shelves for every 420 books, so we will have our first fraction like this:
7/420.
We also have 4 shelves for every x books, so our second fraction will be 4/x.

Set these fractions up as an equation.
7/420 = 4/x

To solve for x, we need to cross multiply the numerators of one fraction with the denominators of the other fraction.
In other words, multiply the top number of one fraction by the bottom number of the other question.

It should look like this:
7(x)
420(4)

7(x) = 7x
420(4) = 1680

Set your products up as an equation.
7x = 1680

Now to solve for x, we need to simplify.
Currently, x is being multiplied by 7.
To get x alone, divide 7x by 7.
Remember, what you do to one side of an equation, you must do to the other, so divide 1680 by 7.

7x / 7 = x
1680 / 7 = 240

You are left with:
x = 240.

For every 4 shelves you have 240 books.

I hope this helps!

You might be interested in
Find the value of x so that L is parallel to M. State the converse used!
galben [10]

Answer:

<h3>6 degrees</h3>

Step-by-step explanation

Find the diagram attached. In Line geometry, there is a theorem that states that the sum of the adjacent interior angles is 180 degrees. According to the diagram, the adjacent interior angles are 7x- 15 and 24x + 9.

The sum of this angles must give 180 degrees as shown;

7x-15 + 24x + 9 = 180

7x+24x-15+9 = 180

31x-6 = 180

31x = 180+6

31x = 186

x = 186/31

x = 6

Hence the value of x is 6 degrees

3 0
2 years ago
What fraction is equivalent to 123.5℅
iVinArrow [24]
123.5%
= 123.5/100
= 1235/1000
= (1235/5) / (1000/5)
= 247/200
= 1 47/200

The final answer is 247/200 or 1 47/200~
5 0
3 years ago
Select all the correct graphs.<br> Choose the graphs that indicate equations with no solution.
Natali [406]

Answer:

The first and last graph.

General Formulas and Concepts:

<u>Algebra I</u>

  • Solving systems of equations graphically

Step-by-step explanation:

In order for a systems of equations to have a solution set, the 2 graphs must intersect at at least 1 point. Here, we see that graphs 1 and 5 do not intersect each other at all.

Therefore, the rest of the graphs have solutions and #1 and #5 do no have any solutions.

3 0
3 years ago
What is an inverse statement
shusha [124]

Answer:

1 | noun | a message that is stated or declared; a communication (oral or written) setting forth particulars or facts etc

2 | noun | a fact or assertion offered as evidence that something is true

3 | noun | (music) the presentation of a musical theme

4 | noun | a nonverbal message

5 | noun | the act of affirming or asserting or stating something

6 | noun | (computer science) a line of code written as part of a computer program

7 | noun | a document showing credits and debits

(7 meanings)

4 0
3 years ago
The equation y=my+b is the slope- intercept form of a linear equation solve y=mc+b for m
SVEN [57.7K]

We need to leave m alone on the right hand side, so let's move everything else to the left hand side.

First of all, we can subtract b from both sides to get

y-b = mc

Now, we can divide both sides by c to get

\dfrac{y-b}{c}=m

And so we solved the expression for m, because we have written an expression in the form m=\ldots, where the right hand side doesn't depend on m.

8 0
3 years ago
Other questions:
  • Convert to rectangular coordinates. use exact values. 7 sqrt 2, 135 degrees
    6·1 answer
  • How many times can 29 fit into 790??
    14·2 answers
  • A triangle has sides with lengths of 45 feet, 76 feet, and 90 feet. Is it a right triangle?
    15·2 answers
  • You have 4/6 of a cup of lemonade concentrate. If you mix 1/3 of a cup of the concentrate with a quart of water you make a small
    7·1 answer
  • Is 7/20 and 0.07 equivalent numbers
    12·2 answers
  • How do you do these
    9·1 answer
  • Can someone answer with steps and explanation? Thanks.
    15·1 answer
  • Claire is going to invest $2,600 and leave it in an account for 18 years. Assuming the interest is compounded continuously, what
    7·2 answers
  • Which is the discriminant of 2x2 - 4x + 7 = 0
    8·1 answer
  • PLEASE HELP a three dight number has one more ten than it has hundreds, and it also has one more than twice as many units as ten
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!